it works (kind of)

src/client/java/danilcus/magnetism/MagnetismClient.java

@@ -1,10 +1,16 @@
 package danilcus.magnetism;
 
+import danilcus.magnetism.entity.SawBladeModel;
+import danilcus.magnetism.entity.SawRenderer;
 import net.fabricmc.api.ClientModInitializer;
+import net.fabricmc.fabric.api.client.rendering.v1.EntityModelLayerRegistry;
+import net.fabricmc.fabric.api.client.rendering.v1.EntityRendererRegistry;
 
 public class MagnetismClient implements ClientModInitializer {
 	@Override
 	public void onInitializeClient() {
 		// This entrypoint is suitable for setting up client-specific logic, such as rendering.
+		EntityRendererRegistry.register(Magnetism.SAW, SawRenderer::new);
+		EntityModelLayerRegistry.registerModelLayer(SawBladeModel.SAWBLADE, SawBladeModel::getTexturedModelData);
 	}
 }

src/client/java/danilcus/magnetism/entity/SawBladeModel.java

@@ -0,0 +1,34 @@
+package danilcus.magnetism.entity;
+
+import danilcus.magnetism.Magnetism;
+import net.minecraft.client.model.*;
+import net.minecraft.client.render.VertexConsumer;
+import net.minecraft.client.render.entity.model.EntityModelLayer;
+import net.minecraft.client.render.entity.model.SinglePartEntityModel;
+import net.minecraft.client.util.math.MatrixStack;
+
+public class SawBladeModel<T extends SawEntity> extends SinglePartEntityModel<T> {
+	private final ModelPart Saw;
+	public SawBladeModel(ModelPart root) {
+		this.Saw = root.getChild("Saw");
+	}
+	public static final EntityModelLayer SAWBLADE = new EntityModelLayer(Magnetism.ID("sawblade"), "main");
+	public static TexturedModelData getTexturedModelData() {
+		ModelData modelData = new ModelData();
+		ModelPartData modelPartData = modelData.getRoot();
+		ModelPartData bb_main = modelPartData.addChild("Saw", ModelPartBuilder.create().uv(-16, 0).cuboid(-8.0F, 0.8F, -8.0F, 16.0F, 0.1F, 16.0F, new Dilation(0.0F)), ModelTransform.pivot(0.0F, 0.0F, 0.0F));
+		return TexturedModelData.of(modelData, 32, 16);
+	}
+	@Override
+	public void setAngles(SawEntity entity, float limbSwing, float limbSwingAmount, float ageInTicks, float netHeadYaw, float headPitch) {
+	}
+	@Override
+	public void render(MatrixStack matrices, VertexConsumer vertexConsumer, int light, int overlay, float red, float green, float blue, float alpha) {
+		Saw.render(matrices, vertexConsumer, light, overlay, red, green, blue, alpha);
+	}
+
+	@Override
+	public ModelPart getPart() {
+		return Saw;
+	}
+}

src/client/java/danilcus/magnetism/entity/SawRenderer.java

@@ -0,0 +1,36 @@
+package danilcus.magnetism.entity;
+
+import danilcus.magnetism.Magnetism;
+import net.minecraft.client.render.OverlayTexture;
+import net.minecraft.client.render.VertexConsumer;
+import net.minecraft.client.render.VertexConsumerProvider;
+import net.minecraft.client.render.entity.EntityRenderer;
+import net.minecraft.client.render.entity.EntityRendererFactory;
+import net.minecraft.client.render.entity.ProjectileEntityRenderer;
+import net.minecraft.client.render.entity.model.TridentEntityModel;
+import net.minecraft.client.render.item.ItemRenderer;
+import net.minecraft.client.util.math.MatrixStack;
+import net.minecraft.entity.projectile.TridentEntity;
+import net.minecraft.util.Identifier;
+import net.minecraft.util.math.MathHelper;
+import net.minecraft.util.math.Vec3f;
+
+public class SawRenderer extends EntityRenderer<SawEntity> {
+    public static final Identifier TEXTURE = Magnetism.ID("textures/entity/saw_blade.png");
+    private final SawBladeModel model;
+
+    public SawRenderer(EntityRendererFactory.Context context) {
+        super(context);
+        this.model = new SawBladeModel<>(context.getPart(SawBladeModel.SAWBLADE));
+    }
+
+    public void render(SawEntity sawEntity, float f, float g, MatrixStack matrixStack, VertexConsumerProvider vertexConsumerProvider, int i) {
+        VertexConsumer vertexConsumer = vertexConsumerProvider.getBuffer(this.model.getLayer(TEXTURE));
+        this.model.render(matrixStack, vertexConsumer, i, OverlayTexture.DEFAULT_UV, 1.0F, 1.0F, 1.0F, 1.0F);
+        super.render(sawEntity, f, g, matrixStack, vertexConsumerProvider, i);
+    }
+
+    public Identifier getTexture(SawEntity entity) {
+        return TEXTURE;
+    }
+}

src/client/resources/magnetism.client.mixins.json

@@ -3,7 +3,6 @@
 	"package": "danilcus.magnetism.mixin.client",
 	"compatibilityLevel": "JAVA_17",
 	"client": [
-		"ExampleClientMixin"
 	],
 	"injectors": {
 		"defaultRequire": 1

src/main/java/danilcus/magnetism/Magnetism.java

@@ -1,22 +1,49 @@
 package danilcus.magnetism;
 
+import danilcus.magnetism.entity.SawEntity;
+import danilcus.magnetism.item.SawBladeItem;
+import danilcus.magnetism.item.SawbladeLauncherItem;
 import net.fabricmc.api.ModInitializer;
 
+import net.fabricmc.fabric.api.item.v1.FabricItemSettings;
+import net.fabricmc.fabric.api.object.builder.v1.entity.FabricEntityTypeBuilder;
+import net.minecraft.entity.EntityDimensions;
+import net.minecraft.entity.EntityType;
+import net.minecraft.entity.SpawnGroup;
+import net.minecraft.item.Item;
+import net.minecraft.item.ItemGroup;
+import net.minecraft.item.ToolMaterials;
+import net.minecraft.util.Identifier;
+import net.minecraft.util.registry.Registry;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 public class Magnetism implements ModInitializer {
 	// This logger is used to write text to the console and the log file.
 	// It is considered best practice to use your mod id as the logger's name.
 	// That way, it's clear which mod wrote info, warnings, and errors.
-    public static final Logger LOGGER = LoggerFactory.getLogger("magnetism");
+	public static final String MOD_ID = "magnetism";
+    public static final Logger LOGGER = LoggerFactory.getLogger(MOD_ID);
+
+	public static final EntityType<SawEntity> SAW = Registry.register(
+			Registry.ENTITY_TYPE,
+			ID("saw_entity"),
+			FabricEntityTypeBuilder.<SawEntity>create(SpawnGroup.MISC, SawEntity::new)
+					.dimensions(EntityDimensions.fixed(1.0f, 0.2F))
+					.build()
+	);
+
+	public static final Item SAWBLADE_LAUNCHER = Registry.register(Registry.ITEM, ID("sawblade_launcher"), new SawbladeLauncherItem(new FabricItemSettings().group(ItemGroup.COMBAT).fireproof()));
+	public static final Item SAW_BLADE = Registry.register(Registry.ITEM, ID("saw_blade"), new SawBladeItem(new FabricItemSettings().group(ItemGroup.COMBAT)));
 
 	@Override
 	public void onInitialize() {
 		// This code runs as soon as Minecraft is in a mod-load-ready state.
 		// However, some things (like resources) may still be uninitialized.
 		// Proceed with mild caution.
+	}
 
-		LOGGER.info("Hello Fabric world!");
+	public static Identifier ID(String path) {
+		return new Identifier(MOD_ID, path);
 	}
 }

src/main/java/danilcus/magnetism/entity/SawEntity.java

@@ -0,0 +1,165 @@
+package danilcus.magnetism.entity;
+
+import com.google.common.collect.Lists;
+import danilcus.magnetism.Magnetism;
+import danilcus.magnetism.item.SawBladeItem;
+import it.unimi.dsi.fastutil.ints.IntOpenHashSet;
+import net.minecraft.advancement.criterion.Criteria;
+import net.minecraft.block.BlockState;
+import net.minecraft.block.Blocks;
+import net.minecraft.enchantment.EnchantmentHelper;
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.EntityType;
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.entity.MovementType;
+import net.minecraft.entity.attribute.EntityAttributes;
+import net.minecraft.entity.damage.DamageSource;
+import net.minecraft.entity.player.PlayerEntity;
+import net.minecraft.entity.projectile.PersistentProjectileEntity;
+import net.minecraft.item.ItemStack;
+import net.minecraft.item.Items;
+import net.minecraft.network.packet.s2c.play.GameStateChangeS2CPacket;
+import net.minecraft.particle.ParticleTypes;
+import net.minecraft.server.network.ServerPlayerEntity;
+import net.minecraft.sound.SoundEvent;
+import net.minecraft.sound.SoundEvents;
+import net.minecraft.util.hit.BlockHitResult;
+import net.minecraft.util.hit.EntityHitResult;
+import net.minecraft.util.hit.HitResult;
+import net.minecraft.util.math.*;
+import net.minecraft.util.shape.VoxelShape;
+import net.minecraft.world.RaycastContext;
+import net.minecraft.world.World;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Arrays;
+import java.util.List;
+
+public class SawEntity extends PersistentProjectileEntity {
+    @Nullable
+    private BlockState inBlockState;
+    private int life;
+    private double damage = 8.0;
+    private int punch;
+
+    public SawEntity(EntityType<? extends PersistentProjectileEntity> entityType, World world) {
+        super(entityType, world);
+    }
+
+    public SawEntity(World world, LivingEntity owner) {
+        super(Magnetism.SAW, owner, world);
+    }
+
+    @Override
+    public void tick() {
+        super.tick();
+
+    }
+
+    @Override
+    protected void onEntityHit(EntityHitResult entityHitResult) {
+        Entity entity = entityHitResult.getEntity();
+        float f = (float)this.getVelocity().length();
+        int i = (int) this.damage;
+
+        Entity entity2 = this.getOwner();
+        DamageSource damageSource;
+        if (entity2 == null) {
+            damageSource = DamageSource.arrow(this, this);
+        } else {
+            damageSource = DamageSource.arrow(this, entity2);
+            if (entity2 instanceof LivingEntity) {
+                ((LivingEntity)entity2).onAttacking(entity);
+            }
+        }
+
+        boolean bl = entity.getType() == EntityType.ENDERMAN;
+        int j = entity.getFireTicks();
+        if (this.isOnFire() && !bl) {
+            entity.setOnFireFor(5);
+        }
+
+        if (entity.damage(damageSource, (float)i)) {
+            if (bl) {
+                return;
+            }
+
+            if (entity instanceof LivingEntity livingEntity) {
+                if (this.punch > 0) {
+                    double d = Math.max(0.0, 1.0 - livingEntity.getAttributeValue(EntityAttributes.GENERIC_KNOCKBACK_RESISTANCE));
+                    Vec3d vec3d = this.getVelocity().multiply(1.0, 0.0, 1.0).normalize().multiply((double)this.punch * 0.6 * d);
+                    if (vec3d.lengthSquared() > 0.0) {
+                        livingEntity.addVelocity(vec3d.x, 0.1, vec3d.z);
+                    }
+                }
+
+                if (!this.world.isClient && entity2 instanceof LivingEntity) {
+                    EnchantmentHelper.onUserDamaged(livingEntity, entity2);
+                    EnchantmentHelper.onTargetDamaged((LivingEntity)entity2, livingEntity);
+                }
+
+                this.onHit(livingEntity);
+                if (livingEntity != entity2 && livingEntity instanceof PlayerEntity && entity2 instanceof ServerPlayerEntity && !this.isSilent()) {
+                    ((ServerPlayerEntity)entity2)
+                            .networkHandler
+                            .sendPacket(new GameStateChangeS2CPacket(GameStateChangeS2CPacket.PROJECTILE_HIT_PLAYER, GameStateChangeS2CPacket.DEMO_OPEN_SCREEN));
+                }
+
+                if (!this.world.isClient && entity2 instanceof ServerPlayerEntity serverPlayerEntity) {
+                    if (!entity.isAlive() && this.isShotFromCrossbow()) {
+                        Criteria.KILLED_BY_CROSSBOW.trigger(serverPlayerEntity, Arrays.asList(entity));
+                    }
+                }
+            }
+
+            this.playSound(this.getSound(), 1.0F, 1.2F / (this.random.nextFloat() * 0.2F + 0.9F));
+        } else {
+            entity.setFireTicks(j);
+            this.setVelocity(this.getVelocity().multiply(-0.1));
+            this.setYaw(this.getYaw() + 180.0F);
+            this.prevYaw += 180.0F;
+            if (!this.world.isClient && this.getVelocity().lengthSquared() < 1.0E-7) {
+                if (this.pickupType == PersistentProjectileEntity.PickupPermission.ALLOWED) {
+                    this.dropStack(this.asItemStack(), 0.1F);
+                }
+
+                this.discard();
+            }
+        }
+    }
+
+    @Override
+    protected void onBlockHit(BlockHitResult blockHitResult) {
+        this.inBlockState = this.world.getBlockState(blockHitResult.getBlockPos());
+        inBlockState.onProjectileHit(this.world, inBlockState, blockHitResult, this);
+        Direction dir = blockHitResult.getSide();
+        if(!this.isShotFromCrossbow() || (dir != Direction.UP && dir != Direction.DOWN) || this.getVelocity().horizontalLength() == 0) {
+            Vec3d vec3d = blockHitResult.getPos().subtract(this.getX(), this.getY(), this.getZ());
+            this.setVelocity(vec3d);
+            Vec3d vec3d2 = vec3d.normalize().multiply(0.05F);
+            this.setPos(this.getX() - vec3d2.x, this.getY() - vec3d2.y, this.getZ() - vec3d2.z);
+            this.playSound(this.getSound(), 1.0F, 1.2F / (this.random.nextFloat() * 0.2F + 0.9F));
+            this.inGround = true;
+            this.shake = 7;
+            this.setCritical(false);
+            this.setSound(SoundEvents.ITEM_TRIDENT_HIT_GROUND);
+            this.setShotFromCrossbow(false);
+        } else {
+            Vec3d vec3d = this.getVelocity();
+            this.setVelocity(vec3d.multiply(0.8d));
+            Vec3d vec3d2 = this.getVelocity();
+            double bounce = Math.abs(vec3d2.x + vec3d2.z) * 1000d * 0.1d;
+            this.setVelocity(vec3d2.x, bounce / 1000d, vec3d2.z);
+            this.playSound(SoundEvents.BLOCK_RESPAWN_ANCHOR_CHARGE, 1.0F, 1.2F / (this.random.nextFloat() * 0.2F + 0.9F));
+        }
+    }
+
+    protected SoundEvent getHitSound() {
+        return SoundEvents.BLOCK_ANVIL_LAND;
+    }
+
+    @Override
+    protected ItemStack asItemStack() {
+        return new ItemStack(Magnetism.SAW_BLADE);
+    }
+}

src/main/java/danilcus/magnetism/item/SawBladeItem.java

@@ -0,0 +1,18 @@
+package danilcus.magnetism.item;
+
+import danilcus.magnetism.entity.SawEntity;
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.entity.projectile.PersistentProjectileEntity;
+import net.minecraft.item.Item;
+import net.minecraft.item.ItemStack;
+import net.minecraft.world.World;
+
+public class SawBladeItem extends Item {
+    public SawBladeItem(Settings settings) {
+        super(settings);
+    }
+
+    public PersistentProjectileEntity createArrow(World world, ItemStack stack, LivingEntity shooter) {
+        return new SawEntity(world, shooter);
+    }
+}