Further work on spell traits and clean up how projectile spells are handled

src/main/java/com/minelittlepony/unicopia/ability/UnicornCastingAbility.java

@@ -8,8 +8,8 @@ import com.google.common.collect.Streams;
 import com.minelittlepony.unicopia.Race;
 import com.minelittlepony.unicopia.ability.data.Hit;
 import com.minelittlepony.unicopia.ability.magic.spell.Spell;
+import com.minelittlepony.unicopia.ability.magic.spell.effect.CustomisedSpellType;
 import com.minelittlepony.unicopia.ability.magic.spell.effect.SpellType;
-import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.item.AmuletItem;
 import com.minelittlepony.unicopia.item.GemstoneItem;
@@ -109,13 +109,13 @@ public class UnicornCastingAbility implements Ability<Hit> {
                 }
             }
         } else {
-            TypedActionResult<SpellType<?>> newSpell = getNewSpell(player);
+            TypedActionResult<CustomisedSpellType<?>> newSpell = getNewSpell(player);
 
             if (newSpell.getResult() != ActionResult.FAIL) {
-                SpellType<?> spell = newSpell.getValue();
+                CustomisedSpellType<?> spell = newSpell.getValue();
 
                 player.subtractEnergyCost(spell.isEmpty() ? 2 : 4);
-                spell.apply(player, SpellTraits.EMPTY);
+                spell.apply(player);
             }
         }
     }
@@ -135,13 +135,13 @@ public class UnicornCastingAbility implements Ability<Hit> {
         return TypedActionResult.pass(stack);
     }
 
-    private TypedActionResult<SpellType<?>> getNewSpell(Pony player) {
+    private TypedActionResult<CustomisedSpellType<?>> getNewSpell(Pony player) {
         final SpellType<?> current = player.getSpellSlot().get(true).map(Spell::getType).orElse(SpellType.empty());
         return Streams.stream(player.getMaster().getItemsHand())
                 .filter(GemstoneItem::isEnchanted)
                 .map(stack -> GemstoneItem.consumeSpell(stack, player.getMaster(), current, null))
                 .findFirst()
-                .orElse(TypedActionResult.<SpellType<?>>pass(current == SpellType.EMPTY_KEY ? SpellType.SHIELD : SpellType.EMPTY_KEY));
+                .orElse(TypedActionResult.<CustomisedSpellType<?>>pass((current == SpellType.EMPTY_KEY ? SpellType.SHIELD : SpellType.EMPTY_KEY).withTraits()));
     }
 
     @Override

src/main/java/com/minelittlepony/unicopia/ability/UnicornProjectileAbility.java

@@ -5,9 +5,8 @@ import org.jetbrains.annotations.Nullable;
 import com.google.common.collect.Streams;
 import com.minelittlepony.unicopia.Race;
 import com.minelittlepony.unicopia.ability.data.Hit;
-import com.minelittlepony.unicopia.ability.magic.spell.ProjectileCapable;
+import com.minelittlepony.unicopia.ability.magic.spell.effect.CustomisedSpellType;
 import com.minelittlepony.unicopia.ability.magic.spell.effect.SpellType;
-import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.item.GemstoneItem;
 import com.minelittlepony.unicopia.particle.MagicParticleEffect;
@@ -63,27 +62,27 @@ public class UnicornProjectileAbility implements Ability<Hit> {
 
     @Override
     public void apply(Pony player, Hit data) {
-        TypedActionResult<SpellType<?>> thrown = getNewSpell(player);
+        TypedActionResult<CustomisedSpellType<?>> thrown = getNewSpell(player);
 
         if (thrown.getResult() != ActionResult.FAIL) {
             @Nullable
-            SpellType<?> spell = thrown.getValue();
+            CustomisedSpellType<?> spell = thrown.getValue();
 
             if (spell == null) {
-                spell = SpellType.VORTEX;
+                spell = SpellType.VORTEX.withTraits();
             }
 
             player.subtractEnergyCost(getCostEstimate(player));
-            ((ProjectileCapable)spell.create(SpellTraits.EMPTY)).toss(player);
+            spell.create().toThrowable().throwProjectile(player);
         }
     }
 
-    private TypedActionResult<SpellType<?>> getNewSpell(Pony player) {
+    private TypedActionResult<CustomisedSpellType<?>> getNewSpell(Pony player) {
         return Streams.stream(player.getMaster().getItemsHand())
                 .filter(GemstoneItem::isEnchanted)
                 .map(stack -> GemstoneItem.consumeSpell(stack, player.getMaster(), null, null))
                 .findFirst()
-                .orElse(TypedActionResult.<SpellType<?>>pass(null));
+                .orElse(TypedActionResult.<CustomisedSpellType<?>>pass(null));
     }
 
     @Override

src/main/java/com/minelittlepony/unicopia/ability/magic/SpellPredicate.java

@@ -2,11 +2,11 @@ package com.minelittlepony.unicopia.ability.magic;
 
 import java.util.function.Predicate;
 
-import com.minelittlepony.unicopia.ability.magic.spell.ProjectileCapable;
+import com.minelittlepony.unicopia.ability.magic.spell.ProjectileSpell;
 import com.minelittlepony.unicopia.ability.magic.spell.Spell;
 
 public interface SpellPredicate<T extends Spell> extends Predicate<Spell> {
-    SpellPredicate<ProjectileCapable> IS_THROWN = s -> s instanceof ProjectileCapable;
+    SpellPredicate<ProjectileSpell> IS_THROWN = s -> s instanceof ProjectileSpell;
     SpellPredicate<Suppressable> IS_SUPPRESSABLE = s -> s instanceof Suppressable;
 
     default boolean isOn(Caster<?> caster) {

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/AbstractDelegatingSpell.java

@@ -10,13 +10,14 @@ import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.spell.effect.SpellType;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.projectile.MagicProjectileEntity;
+import com.minelittlepony.unicopia.projectile.ProjectileDelegate;
 
 import net.minecraft.block.BlockState;
 import net.minecraft.entity.Entity;
 import net.minecraft.nbt.NbtCompound;
 import net.minecraft.util.math.BlockPos;
 
-public abstract class AbstractDelegatingSpell implements Spell, ProjectileCapable {
+public abstract class AbstractDelegatingSpell implements ProjectileSpell {
 
     private boolean isDirty;
 
@@ -76,27 +77,30 @@ public abstract class AbstractDelegatingSpell implements Spell, ProjectileCapabl
         getDelegates().forEach(spell -> spell.onDestroyed(caster));
     }
 
+    @Override
+    public boolean tick(Caster<?> source, Situation situation) {
+        return execute(getDelegates().stream(), spell -> spell.tick(source, situation));
+    }
+
     @Override
     public void onImpact(MagicProjectileEntity projectile, BlockPos pos, BlockState state) {
-        getDelegates().stream().filter(a -> a instanceof ProjectileCapable).forEach(a -> {
+        getDelegates().stream().filter(a -> a instanceof ProjectileDelegate).forEach(a -> {
-            ((ProjectileCapable)a).onImpact(projectile, pos, state);
+            ((ProjectileDelegate)a).onImpact(projectile, pos, state);
         });
     }
 
     @Override
     public void onImpact(MagicProjectileEntity projectile, Entity entity) {
-        getDelegates().stream().filter(a -> a instanceof ProjectileCapable).forEach(a -> {
+        getDelegates().stream().filter(a -> a instanceof ProjectileDelegate).forEach(a -> {
-            ((ProjectileCapable)a).onImpact(projectile, entity);
+            ((ProjectileDelegate)a).onImpact(projectile, entity);
         });
     }
 
     @Override
-    public boolean tick(Caster<?> source, Situation situation) {
+    public void configureProjectile(MagicProjectileEntity projectile, Caster<?> caster) {
-        return execute(getDelegates().stream(), spell -> spell.tick(source, situation));
+        getDelegates().stream().filter(a -> a instanceof ProjectileSpell).forEach(a -> {
-    }
+            ((ProjectileSpell)a).configureProjectile(projectile, caster);
-
+        });
-    private boolean execute(Stream<Spell> spells, Function<Spell, Boolean> action) {
-        return spells.reduce(false, (u, a) -> action.apply(a), (a, b) -> a || b);
     }
 
     @Override
@@ -111,4 +115,8 @@ public abstract class AbstractDelegatingSpell implements Spell, ProjectileCapabl
             uuid = compound.getUuid("uuid");
         }
     }
+
+    private static boolean execute(Stream<Spell> spells, Function<Spell, Boolean> action) {
+        return spells.reduce(false, (u, a) -> action.apply(a), (a, b) -> a || b);
+    }
 }

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/CompoundSpell.java

@@ -26,8 +26,8 @@ public class CompoundSpell extends AbstractDelegatingSpell {
 
     @Override
     public Spell combineWith(Spell other) {
-        if (other instanceof CompoundSpell) {
+        if (other instanceof AbstractDelegatingSpell) {
-            spells.addAll(((CompoundSpell)other).spells);
+            spells.addAll(((AbstractDelegatingSpell)other).getDelegates());
         } else {
             spells.add(other);
         }

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/PlaceableSpell.java

@@ -86,7 +86,7 @@ public class PlaceableSpell extends AbstractDelegatingSpell {
                 spawner.addParticle(new OrientedBillboardParticleEffect(UParticles.MAGIC_RUNES, 90, 0), source.getOriginVector(), Vec3d.ZERO);
             }).ifPresent(p -> {
                 p.attach(source);
-                p.setAttribute(1, getType().getColor());
+                p.setAttribute(1, spell.getType().getColor());
             });
         }
 

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/ProjectileCapable.java

@@ -1,88 +0,0 @@
-package com.minelittlepony.unicopia.ability.magic.spell;
-
-import org.jetbrains.annotations.Nullable;
-
-import com.minelittlepony.unicopia.ability.magic.Caster;
-import com.minelittlepony.unicopia.item.GemstoneItem;
-import com.minelittlepony.unicopia.item.UItems;
-import com.minelittlepony.unicopia.projectile.MagicProjectileEntity;
-import com.minelittlepony.unicopia.projectile.ProjectileDelegate;
-
-import net.minecraft.block.BlockState;
-import net.minecraft.entity.Entity;
-import net.minecraft.entity.LivingEntity;
-import net.minecraft.item.ItemStack;
-import net.minecraft.sound.SoundCategory;
-import net.minecraft.sound.SoundEvent;
-import net.minecraft.sound.SoundEvents;
-import net.minecraft.util.math.BlockPos;
-import net.minecraft.world.World;
-
-/**
- * Magic effects that can be thrown.
- */
-public interface ProjectileCapable extends Spell, ProjectileDelegate {
-
-    @Override
-    default void onImpact(MagicProjectileEntity projectile, BlockPos pos, BlockState state) {
-        if (!projectile.isClient()) {
-            tick(projectile, Situation.PROJECTILE);
-        }
-    }
-
-    @Override
-    default void onImpact(MagicProjectileEntity projectile, Entity entity) {
-
-    }
-
-    /**
-     * The amount of damage to be dealt when the projectile collides with an entity.
-     */
-    default int getThrowDamage(Caster<?> stack) {
-        return 0;
-    }
-
-    /**
-     * The sound made when thrown.
-     */
-    default SoundEvent getThrowSound(Caster<?> caster) {
-        return SoundEvents.ITEM_CHORUS_FRUIT_TELEPORT;
-    }
-
-    /**
-     * Gets the appearance to be used when projecting this spell.
-     */
-    default ItemStack getCastAppearance(Caster<?> caster) {
-        return GemstoneItem.enchanted(UItems.GEMSTONE.getDefaultStack(), getType());
-    }
-
-    /**
-     * Projects this spell.
-     *
-     * Returns the resulting projectile entity for customization (or null if on the client).
-     */
-    @Nullable
-    default MagicProjectileEntity toss(Caster<?> caster) {
-        World world = caster.getWorld();
-
-        LivingEntity entity = caster.getMaster();
-
-        world.playSound(null, entity.getX(), entity.getY(), entity.getZ(), getThrowSound(caster), SoundCategory.NEUTRAL, 0.7F, 0.4F / (world.random.nextFloat() * 0.4F + 0.8F));
-
-        if (!caster.isClient()) {
-            MagicProjectileEntity projectile = new MagicProjectileEntity(world, entity);
-
-            projectile.setItem(getCastAppearance(caster));
-            projectile.setThrowDamage(getThrowDamage(caster));
-            projectile.setSpell(this);
-            projectile.setHydrophobic();
-            projectile.setProperties(entity, entity.getPitch(), entity.getYaw(), 0, 1.5F, 1);
-
-            world.spawnEntity(projectile);
-
-            return projectile;
-        }
-
-        return null;
-    }
-}

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/ProjectileSpell.java

@@ -0,0 +1,23 @@
+package com.minelittlepony.unicopia.ability.magic.spell;
+
+import com.minelittlepony.unicopia.ability.magic.Caster;
+import com.minelittlepony.unicopia.projectile.MagicProjectileEntity;
+import com.minelittlepony.unicopia.projectile.ProjectileDelegate;
+
+import net.minecraft.block.BlockState;
+import net.minecraft.util.math.BlockPos;
+
+/**
+ * Magic effects that can be thrown.
+ */
+public interface ProjectileSpell extends Spell, ProjectileDelegate {
+
+    @Override
+    default void onImpact(MagicProjectileEntity projectile, BlockPos pos, BlockState state) {
+        if (!projectile.isClient()) {
+            tick(projectile, Situation.PROJECTILE);
+        }
+    }
+
+    default void configureProjectile(MagicProjectileEntity projectile, Caster<?> caster) { }
+}

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/Spell.java

@@ -75,4 +75,12 @@ public interface Spell extends NbtSerialisable, Affine {
     default PlaceableSpell toPlaceable() {
         return SpellType.PLACED_SPELL.create(SpellTraits.EMPTY).setSpell(this);
     }
+
+    /**
+     * Converts this spell into a throwable spell.
+     * @return
+     */
+    default ThrowableSpell toThrowable() {
+        return SpellType.THROWN_SPELL.create(SpellTraits.EMPTY).setSpell(this);
+    }
 }

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/ThrowableSpell.java

@@ -0,0 +1,69 @@
+package com.minelittlepony.unicopia.ability.magic.spell;
+
+import java.util.Collection;
+import java.util.List;
+import java.util.Optional;
+
+import com.minelittlepony.unicopia.ability.magic.Caster;
+import com.minelittlepony.unicopia.ability.magic.spell.effect.SpellType;
+import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
+import com.minelittlepony.unicopia.item.GemstoneItem;
+import com.minelittlepony.unicopia.item.UItems;
+import com.minelittlepony.unicopia.projectile.MagicProjectileEntity;
+
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.sound.SoundCategory;
+import net.minecraft.sound.SoundEvents;
+import net.minecraft.world.World;
+
+public class ThrowableSpell extends AbstractDelegatingSpell {
+
+    private Spell spell;
+
+    public ThrowableSpell(SpellType<?> type, SpellTraits traits) {
+        super(type, traits);
+    }
+
+    public ThrowableSpell setSpell(Spell spell) {
+        this.spell = spell;
+        return this;
+    }
+
+    @Override
+    protected Collection<Spell> getDelegates() {
+        return List.of(spell);
+    }
+
+    /**
+     * Projects this spell.
+     *
+     * Returns the resulting projectile entity for customization (or null if on the client).
+     */
+    public Optional<MagicProjectileEntity> throwProjectile(Caster<?> caster) {
+        World world = caster.getWorld();
+
+        LivingEntity entity = caster.getMaster();
+
+        world.playSound(null, entity.getX(), entity.getY(), entity.getZ(), SoundEvents.ITEM_CHORUS_FRUIT_TELEPORT, SoundCategory.NEUTRAL, 0.7F, 0.4F / (world.random.nextFloat() * 0.4F + 0.8F));
+
+        if (!caster.isClient()) {
+            MagicProjectileEntity projectile = new MagicProjectileEntity(world, entity);
+
+            projectile.setItem(GemstoneItem.enchanted(UItems.GEMSTONE.getDefaultStack(), spell.getType()));
+            projectile.setSpell(this);
+            projectile.setProperties(entity, entity.getPitch(), entity.getYaw(), 0, 1.5F, 1);
+            projectile.setHydrophobic();
+            configureProjectile(projectile, caster);
+            world.spawnEntity(projectile);
+
+            return Optional.of(projectile);
+        }
+
+        return Optional.empty();
+    }
+
+    @Override
+    public ThrowableSpell toThrowable() {
+        return this;
+    }
+}

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/AwkwardSpell.java

@@ -5,7 +5,6 @@ import java.util.List;
 
 import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.spell.Situation;
-import com.minelittlepony.unicopia.ability.magic.spell.ProjectileCapable;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.util.shape.Sphere;
 
@@ -17,7 +16,7 @@ import net.minecraft.util.math.MathHelper;
 import net.minecraft.util.math.Vec3d;
 import net.minecraft.util.registry.Registry;
 
-public class AwkwardSpell extends AbstractSpell implements ProjectileCapable {
+public class AwkwardSpell extends AbstractSpell {
 
     protected AwkwardSpell(SpellType<?> type, SpellTraits traits) {
         super(type, traits);

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/CustomisedSpellType.java

@@ -0,0 +1,31 @@
+package com.minelittlepony.unicopia.ability.magic.spell.effect;
+
+import org.jetbrains.annotations.Nullable;
+
+import com.minelittlepony.unicopia.ability.magic.Caster;
+import com.minelittlepony.unicopia.ability.magic.spell.Spell;
+import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
+
+public class CustomisedSpellType<T extends Spell> {
+
+    private final SpellType<T> type;
+    private final SpellTraits traits;
+
+    public CustomisedSpellType(SpellType<T> type, SpellTraits traits) {
+        this.type = type;
+        this.traits = traits;
+    }
+
+    public boolean isEmpty() {
+        return type.isEmpty();
+    }
+
+    public T create() {
+        return type.create(traits);
+    }
+
+    @Nullable
+    public T apply(Caster<?> caster) {
+        return type.apply(caster, traits);
+    }
+}

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/FireSpell.java

@@ -3,7 +3,7 @@ package com.minelittlepony.unicopia.ability.magic.spell.effect;
 import com.minelittlepony.unicopia.EquinePredicates;
 import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.spell.Situation;
-import com.minelittlepony.unicopia.ability.magic.spell.ProjectileCapable;
+import com.minelittlepony.unicopia.ability.magic.spell.ProjectileSpell;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.block.state.StateMaps;
 import com.minelittlepony.unicopia.particle.ParticleUtils;
@@ -35,7 +35,7 @@ import net.minecraft.world.explosion.Explosion.DestructionType;
 /**
  * Simple fire spell that triggers an effect when used on a block.
  */
-public class FireSpell extends AbstractSpell implements ProjectileCapable {
+public class FireSpell extends AbstractSpell implements ProjectileSpell {
 
     private static final Shape EFFECT_RANGE = new Sphere(false, 4);
 

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/IceSpell.java

@@ -2,7 +2,6 @@ package com.minelittlepony.unicopia.ability.magic.spell.effect;
 
 import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.spell.Situation;
-import com.minelittlepony.unicopia.ability.magic.spell.ProjectileCapable;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.block.state.StateMaps;
 import com.minelittlepony.unicopia.particle.ParticleUtils;
@@ -27,7 +26,7 @@ import net.minecraft.util.math.BlockPos;
 import net.minecraft.util.math.Vec3d;
 import net.minecraft.world.World;
 
-public class IceSpell extends AbstractSpell implements ProjectileCapable {
+public class IceSpell extends AbstractSpell {
 
     private final int rad = 3;
     private final Shape effect_range = new Sphere(false, rad);

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/RevealingSpell.java

@@ -3,7 +3,6 @@ package com.minelittlepony.unicopia.ability.magic.spell.effect;
 import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.SpellPredicate;
 import com.minelittlepony.unicopia.ability.magic.spell.Situation;
-import com.minelittlepony.unicopia.ability.magic.spell.ProjectileCapable;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.particle.MagicParticleEffect;
 import com.minelittlepony.unicopia.util.shape.Shape;
@@ -16,7 +15,7 @@ import net.minecraft.util.math.Vec3d;
 /**
  * A spell for revealing changelings.
  */
-public class RevealingSpell extends AbstractSpell implements ProjectileCapable {
+public class RevealingSpell extends AbstractSpell {
     private static final Shape AREA = new Sphere(false, 15);
 
     protected RevealingSpell(SpellType<?> type, SpellTraits traits) {

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/ScorchSpell.java

@@ -1,7 +1,5 @@
 package com.minelittlepony.unicopia.ability.magic.spell.effect;
 
-import org.jetbrains.annotations.Nullable;
-
 import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.spell.Situation;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
@@ -42,14 +40,7 @@ public class ScorchSpell extends FireSpell {
     }
 
     @Override
-    @Nullable
+    public void configureProjectile(MagicProjectileEntity projectile, Caster<?> caster) {
-    public MagicProjectileEntity toss(Caster<?> caster) {
-        MagicProjectileEntity projectile = super.toss(caster);
-
-        if (projectile != null) {
         projectile.setNoGravity(true);
     }
-
-        return projectile;
-    }
 }

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/ShieldSpell.java

@@ -10,7 +10,7 @@ import com.minelittlepony.unicopia.EquinePredicates;
 import com.minelittlepony.unicopia.Unicopia;
 import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.spell.Situation;
-import com.minelittlepony.unicopia.ability.magic.spell.ProjectileCapable;
+import com.minelittlepony.unicopia.ability.magic.spell.ProjectileSpell;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.entity.player.Pony;
 import com.minelittlepony.unicopia.item.FriendshipBraceletItem;
@@ -35,7 +35,7 @@ import net.minecraft.entity.vehicle.BoatEntity;
 import net.minecraft.sound.SoundEvents;
 import net.minecraft.util.math.Vec3d;
 
-public class ShieldSpell extends AbstractSpell implements ProjectileCapable {
+public class ShieldSpell extends AbstractSpell implements ProjectileSpell {
 
     private final ParticleHandle particlEffect = new ParticleHandle();
 

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/SpellType.java

@@ -17,6 +17,7 @@ import com.minelittlepony.unicopia.ability.magic.spell.DisguiseSpell;
 import com.minelittlepony.unicopia.ability.magic.spell.JoustingSpell;
 import com.minelittlepony.unicopia.ability.magic.spell.PlaceableSpell;
 import com.minelittlepony.unicopia.ability.magic.spell.Spell;
+import com.minelittlepony.unicopia.ability.magic.spell.ThrowableSpell;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.util.Registries;
 
@@ -37,6 +38,7 @@ public final class SpellType<T extends Spell> implements Affine, SpellPredicate<
 
     public static final SpellType<CompoundSpell> COMPOUND_SPELL = register("compound", Affinity.NEUTRAL, 0, false, CompoundSpell::new);
     public static final SpellType<PlaceableSpell> PLACED_SPELL = register("placed", Affinity.NEUTRAL, 0, false, PlaceableSpell::new);
+    public static final SpellType<ThrowableSpell> THROWN_SPELL = register("thrown", Affinity.NEUTRAL, 0, false, ThrowableSpell::new);
 
     public static final SpellType<DisguiseSpell> DISGUISE = register("disguise", Affinity.BAD, 0x19E48E, false, DisguiseSpell::new);
     public static final SpellType<JoustingSpell> RAINBOOM = register("rainboom", Affinity.GOOD, 0xBDBDF9, false, JoustingSpell::new);
@@ -66,12 +68,15 @@ public final class SpellType<T extends Spell> implements Affine, SpellPredicate<
     @Nullable
     private String translationKey;
 
+    private final CustomisedSpellType<T> traited;
+
     private SpellType(Identifier id, Affinity affinity, int color, boolean obtainable, Factory<T> factory) {
         this.id = id;
         this.affinity = affinity;
         this.color = color;
         this.obtainable = obtainable;
         this.factory = factory;
+        traited = new CustomisedSpellType<>(this, SpellTraits.EMPTY);
     }
 
     public boolean isObtainable() {
@@ -105,6 +110,14 @@ public final class SpellType<T extends Spell> implements Affine, SpellPredicate<
         return new TranslatableText(getTranslationKey());
     }
 
+    public CustomisedSpellType<T> withTraits() {
+        return traited;
+    }
+
+    public CustomisedSpellType<T> withTraits(SpellTraits traits) {
+        return traits.isEmpty() ? withTraits() : new CustomisedSpellType<>(this, traits);
+    }
+
     @Nullable
     public T create(SpellTraits traits) {
         try {

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/TransformationSpell.java

@@ -9,7 +9,7 @@ import java.util.Set;
 import com.minelittlepony.unicopia.UTags;
 import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.spell.Situation;
-import com.minelittlepony.unicopia.ability.magic.spell.ProjectileCapable;
+import com.minelittlepony.unicopia.ability.magic.spell.ProjectileSpell;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 import com.minelittlepony.unicopia.entity.UEntities;
 import com.minelittlepony.unicopia.particle.ParticleUtils;
@@ -22,7 +22,7 @@ import net.minecraft.particle.ParticleTypes;
 import net.minecraft.sound.SoundEvents;
 import net.minecraft.util.Util;
 
-public class TransformationSpell extends AbstractSpell implements ProjectileCapable {
+public class TransformationSpell extends AbstractSpell implements ProjectileSpell {
 
     protected TransformationSpell(SpellType<?> type, SpellTraits traits) {
         super(type, traits);

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/trait/SpellTraits.java

@@ -43,19 +43,19 @@ public final class SpellTraits {
         return nbt;
     }
 
-    public Optional<SpellTraits> of(Collection<ItemStack> stacks) {
+    public static Optional<SpellTraits> of(Collection<ItemStack> stacks) {
         return fromEntries(stacks.stream().flatMap(a -> of(a).entries().stream()));
     }
 
-    public SpellTraits of(ItemStack stack) {
+    public static SpellTraits of(ItemStack stack) {
         return getEmbeddedTraits(stack).orElseGet(() -> of(stack.getItem()));
     }
 
-    public SpellTraits of(Item item) {
+    public static SpellTraits of(Item item) {
         return TraitLoader.INSTANCE.values.getOrDefault(Registry.ITEM.getId(item), null);
     }
 
-    public SpellTraits of(Block block) {
+    public static SpellTraits of(Block block) {
         return of(block.asItem());
     }
 

src/main/java/com/minelittlepony/unicopia/item/GemstoneItem.java

@@ -9,7 +9,9 @@ import org.jetbrains.annotations.Nullable;
 import com.minelittlepony.unicopia.Affinity;
 import com.minelittlepony.unicopia.Unicopia;
 import com.minelittlepony.unicopia.ability.magic.spell.Spell;
+import com.minelittlepony.unicopia.ability.magic.spell.effect.CustomisedSpellType;
 import com.minelittlepony.unicopia.ability.magic.spell.effect.SpellType;
+import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
 
 import net.minecraft.client.item.TooltipContext;
 import net.minecraft.entity.player.PlayerEntity;
@@ -79,19 +81,20 @@ public class GemstoneItem extends Item {
         return super.getName();
     }
 
-    public static TypedActionResult<SpellType<?>> consumeSpell(ItemStack stack, PlayerEntity player, @Nullable SpellType<?> exclude, @Nullable Predicate<SpellType<?>> test) {
+    public static TypedActionResult<CustomisedSpellType<?>> consumeSpell(ItemStack stack, PlayerEntity player, @Nullable SpellType<?> exclude, @Nullable Predicate<SpellType<?>> test) {
 
         if (!isEnchanted(stack)) {
             return TypedActionResult.pass(null);
         }
 
         SpellType<Spell> key = getSpellKey(stack);
+        SpellTraits traits = SpellTraits.of(stack);
 
         if (Objects.equals(key, exclude)) {
             return TypedActionResult.fail(null);
         }
 
-        if (key == SpellType.EMPTY_KEY || (test == null || !test.test(key))) {
+        if (key.isEmpty() || (test == null || !test.test(key))) {
             return TypedActionResult.fail(null);
         }
 
@@ -105,7 +108,7 @@ public class GemstoneItem extends Item {
             }
         }
 
-        return TypedActionResult.consume(key);
+        return TypedActionResult.consume(key.withTraits(traits));
     }
 
     public static boolean isEnchanted(ItemStack stack) {

src/main/java/com/minelittlepony/unicopia/projectile/ProjectileDelegate.java

@@ -8,10 +8,10 @@ public interface ProjectileDelegate {
     /**
      * Called once the projectile lands either hitting the ground or an entity.
      */
-    void onImpact(MagicProjectileEntity projectile, BlockPos pos, BlockState state);
+    default void onImpact(MagicProjectileEntity projectile, BlockPos pos, BlockState state) {}
 
     /**
      * Called once the projectile lands either hitting the ground or an entity.
      */
-    void onImpact(MagicProjectileEntity projectile, Entity entity);
+    default void onImpact(MagicProjectileEntity projectile, Entity entity) {}
 }