Mobs Mob Spawning Hostile Mobs Creeper farming Wither (Boss) (WORK IN PROGRESS) The Wither Boss or more commonly known as the wither, is a player constructed flying mob with immense destructive capabilities. It can be constructed with 4 soul sand in a T shape and 3 wither skulls overlaying the top. (Note: This can be reconfigured in many ways as long as it remains a T and the skulls line what would be the top relative for that position.)  The wither has different HP for different difficulties:  Easy: 300 Normal: 450   Hard: 600   The wither has two distinct stages:  Stage 1:  The wither flies when it sees a target or is trying to pathfind somewhere and will shoot out 1 dangerous wither skull passively every ~15 seconds. If it finds a target it will lock onto that target and rarely redirect unless the target is unable to be reached or shot at. It will begin its firing cycle when it locked onto a given target. When the wither is hurt in this phase it will break a 4x6x4 shape out of the blocks around itself dropping their items 20 ticks after the attack and fire out a single dangerous wither skull. The wither will be in the northwest corner of the center 4 blocks when this happens. Stage 2: This stage is indicated by the glowing "Shield" around itself and the summoning of 3 wither skeletons on its position this stage happens when the wither reaches half health. The wither will then begin its charge attack where it will charge at a given target breaking a 6x8x6 cuboid around itself every tick until the charge as stopped which lasts around 1 second (20 ticks) the wither will again be in the northwest corner of the center 4 blocks. The wither will also no longer use its break attack when hurt only during the charge. Another thing to note is the wither cannot be harmed with projectiles in this phase. The wither shoots out two types of flying projectiles: wither_skull This skull can penetrate through limited blocks. It has a low blast power akin to the ghast fireball explosion. It is fired out of the host wither quite fast and cannot be redirected with a hit. wither_skull_dangerous    This skull can penetrate through almost any block minus a few exceptions: bedrock, reinforced deepslate, command blocks, barriers, water logged blocks, moving blocks, end frame, light blocks, end portal tile, structure blocks, and end gateways. It can be redirected with a hit and is fired out of the wither at a slower pace than its counterpart.   The projectiles can be fired out either passively, when the wither is harmed, or in its firing cycle. The firing cycle consists of firing 3 wither skulls and 1 wither skull dangerous at the end. The time in between these skulls is dependent on how much damage the wither has sustained and if done right through healing the wither and then attacking again its firing rate can get up to 1 skull per tick. Each firing cycle has a 7 second intermediate period where the wither does not start firing until the cycle starts again. Passive Mobs Squid farming Mob Pathfinding A section describing how Mobs find goals and targets to attempt to move towards. Entity NBT About how entity NBTs and the different types there are. NBT What is NBT NBT or Named Binary Tag, is a tree-like structure that Minecraft uses to store entity data. This data can include  attributes, definitions, and identifier information. This information can control things what the entity looks like, how it interacts with the world, and its behavior. Knowing how NBT works can give you insight on certain things you may encounter or want to achieve. NBT however is not the entity itself but instead a snapshot of its runtime components that we can load to make a copy of the entity. In bedrock all NBT is encoded in little-endian which is important if you want to extract it into a stringified format like the one below. Entity NBT Format NBT FORMAT (WIP) Legend Icon Meaning String Short Long Array Long JSON Object Integer Array Integer Float Double Byte Array Byte Boolean Array Format Tree root label Where the NBT tree starts identifier Defines entity type ID. Example: "minecraft:pig". definitions Adds or removes components from the from the baseline entity components. These are entity mostly specific. + adds a component not on the base entity and - removes a component on the base entity. Example: "+minecraft:can_ride_default" UniqueID Unique numerical ID of the entity used to identify it from others of it type. Example: "-4294967289". Pos Shows numerical values as to the position of the entity in 3D space. X Shows the X position of the entity. Y Shows the Y position of the entity. Z Shows the Z position of the entity. Rotation Defines the orientation angle of the entity.  Yaw The orientation of the entity rotating clockwise around the X axis. (No more than 360°) Pitch The orientation of the entity rotating up and down along the Y axis. (No more than ±90°) Motion Defines the momentum assigned to a given entity. dX Defines momentum along the X axis. dY Defines momentum along the Y axis. dZ Defines momentum along the Z axis. CustomNameVisible Shows a custom name given to an entity regardless if you are looking directly at them or not. LastDimensionId Last dimension visited by the entity. (Seemingly deprecated) FallDistance Distance the entity has fallen. Fire Number of ticks till the fire on the entity is extinguished. OnGround Defines if an entity is in the state of being on the ground. (Not falling) Invulnerable Makes the target entity unable to be harmed by any natural source. Entities with this tag cannot be moved by fishing rods. Creative players can deal damage regardless of the tag being applied to the target entity. PortalCooldown Number of ticks before a given entity can use a nether portal again. IsGlobal Defines if the entity can function in unloaded chunks. IsAutonomous Exact use is unknown. LinksTag Defines a connection between a ride and a rider.  entityID Unique numerical ID of the rider entity the ride entity has linked to. Example: "-3410204032983". linkID Numerical value used to determine which rider is which on the ride entity. (Starts at 0 and increments by 1 for each passenger)  LootDropped Defines if an entity can or cannot drop loot. This is applied after the entity has received the Dead tag to ensure it doesn't drop loot more than once. Color Defines an entities color type. For example the difference between a black cat and a siamese cat is this value. Color2 Defines an entities secondary color. Only tropical fish use this. Strength Defines how much a llama can carry. ( 3 * number = Items carriable )  StrengthMax Does the same thing as " Strength" seemingly. Sheared Defines whether a sheep is sheared.  IsIllagerCaptain Defines whether an entity is an Illager Captain. OwnerNew Shows new owner ID. This is often for projectiles.   Example: "-4294967295" OwnerID Shows current owner ID. This is often for projectiles.   Example: "-4294967295" Sitting Defines whether an entity is sitting. IsBaby Defines whether an entity is in its baby variant. IsTamed Defines whether an entity is tame. IsTrusting Defines whether an entity is trusting of the player. IsOrphaned Defines whether an entity is spawned without parents. IsAngry Defines whether an entity is hostile when it is normally neutral. IsOutOfControl Is set to true when a player is controlling it and it is a ship. Variant Defines entity variant type. MarkVariant Defines the mark variant of an entity.  Saddled Is set to true when a player has mounted it and it is a living entity. IsChested Defines if a working animal such as a horse carries a chest on its back. ShowBottom Defines whether an end crystal shows the bedrock slab below it. (Used in the end dimension's crystals) IsGliding Defines whether an entity is in the gliding state with an elytra. IsSwiming Defines whether an entity is in the swimming state. IsEating Defines whether an entity is eating something. IsScared Defines whether an entity is in the scared state. IsStunned Defines whether ravager is stunned. IsRoaring Defines whether ravager is roaring. SkinID Defines a villager/zombie villagers skin texture. Persistent Defines if an entity can or cannot despawn when out of the player's mob spawning radius. Tags Holds player applied tags that an entity has. (these are applied via /tag) tag (not a real namespace) Tag identifier   Example: "CanopyAdmin" CustomDisplayTile Set to true when a minecart is displaying a custom block. DisplayBlock Set to true when a minecart is displaying a custom block. block (not a real namespace) Block ID of a block to be displayed within the minecart.   Example: "minecraft:dirt" DisplayOffset Number of pixels the display block of a minecart is offset along the Y axis. Willing Defines if a villager is willing to breed or not. This value is set to false for a period of time after breeding. SpawnedByNight Defines if a mob was spawned naturally by the night cycle or not. ItemInHand Defines what item an entity holding. Count Count of items in the hand. Name Defines the item type in the hand.   Example: "minecraft:crossbow" WasPickedUp Defines if the entity got the item by picking it up. Damage This may say damage but it does not store the damage for the item. CanPlaceOn Defines what the item be placed on when the user is in Adventure mode. block (not real namespace) Block ID it can be placed on.   Example: "minecraft:stone" CanDestroy Defines what the item can break when the user is in Adventure mode. block (Not real namespace) Block ID it can destroy.   Example: "minecraft:stone" tag Defines additional properties. Mainhand Defines what item is in the entities mainhand. item (not a real namespace) Item object. Count Count of items. Name Defines the item type.   Example: "minecraft:crossbow" WasPickedUp Defines if the entity got the item by picking it up. Damage This may say damage but it does not store the damage for the item. CanPlaceOn Defines what the item be placed on when the user is in Adventure mode. block (not real namespace) Block ID it can be placed on.   Example: "minecraft:stone" CanDestroy Defines what the item can break when the user is in Adventure mode. block (Not real namespace) Block ID it can destroy.   Example: "minecraft:stone" tag Defines additional properties. Offhand Defines what item is in the entities offhand. item (not a real namespace) Item object. Count Count of items. Name Defines the item type.   Example: "minecraft:crossbow" WasPickedUp Defines if the entity got the item by picking it up. Damage This may say damage but it does not store the damage for the item. CanPlaceOn Defines what the item be placed on when the user is in Adventure mode. block (not real namespace) Block ID it can be placed on.   Example: "minecraft:stone" CanDestroy Defines what the item can break when the user is in Adventure mode. block (Not real namespace) Block ID it can destroy.   Example: "minecraft:stone" tag Defines additional properties. limitedLife Sets a number of ticks before an entity is deleted.  TradeTier Defines a villagers trading level. TradeExperience Defines a villagers experience progress to next level. canPickupItems Defines if an entity can pick up items. hasSetCanPickupItems Set to true if the canPickupItems component has been set by the game. HurtTime Duration an entity has the invulnerable tag set to true after taking damage. This also controls the duration in which the entity is red after taking damage. DeathTime Duration an entity executes its death animation to the player before deletion.  Dead Defines if the entity has died. AttackTime Ticks before attack cooldown is complete. Surface True if the entity has spawned naturally on the surface. (IE, surface cap) portal_transition Internally used entity NBT for transitioning entities between dimensions. This is used because when an entity enters the portal it's reference is destroyed, so it needs some way to know the conditions in which it entered the portal. axis Saves the the axis in which the portal the entity entered is facing. (1 = z, 2 = x) dimension Defines which dimension the entity is coming from (0 = overworld, 1 = nether, 2 = end) X Shows the X position the entity entered a portal at. Y Shows the Y position the entity entered a portal at. Z Shows the Z position the entity entered a portal at. NaturalSpawn True if the entity has spawned naturally via cave or surface cap. TargetID Unique numerical ID of an entity that this entity is targeting for some purpose. ActiveEffects Lists the entities potion effects it has on it. Effect (Not A Real Namespace) Effect json object Ambient True if the effect was applied by a beacon. This is to make the particles less invasive on the screen. Amplifier The potion effect level. 0 is level 1. DisplayOnScreenTextureAnimation Displays a screen animation when an effect is applied. This is used in bad omen, totems, and the hero of the village to display the floating icon once you get the effect. Duration Number of ticks before the effect wears off. DurationEasy Number of ticks before the effect wears off for Easy mode. DurationNormal Number of ticks before the effect wears off for Normal mode. DurationNormal Number of ticks before the effect wears off for Hard mode. Id Numerical potion Id.   example: 28 ShowParticles Defines if particles are shown or not. FactorCalculationData Unknown usage change_timestamp Unknown factor_current Unknown factor_previous Unknown factor_start Unknown factor_target Unknown had_applied Unknown had_last_tick Unknown padding_duration Unknown IsInRaid Boolean only present in villagers that defines if the villager is currently in a raid. ReactToBell Defines if a villager will react to a bell ringing and go to its home or not. TargetCaptainID Unique numerical ID of the Illager captain of a patrol. Used by pillagers in patrols. Example: "-4294967289". isCreative Defines if a given projectile was fired from a player in creative mode. (Only projectiles have this) enchantPower Defines the power level given to an arrow by the power enchantment on the shooters bow. enchantPunch Defines the punch level given to an arrow by the power enchantment on the shooters bow. enchantFlame Defines the flame level given to an arrow by the power enchantment on the shooters bow. enchantInfinity Defines the infinity level given to an arrow by the power enchantment on the shooters bow. MobEffects List of effects that a given entity can pass onto others. This does not apply to itself. (Used in area effect clouds and tipped arrows) Effect (Not A Real Namespace) Effect json object Ambient True if the effect was applied by a beacon. This is to make the particles less invasive on the screen. Amplifier The potion effect level. 0 is level 1. DisplayOnScreenTextureAnimation Displays a screen animation when an effect is applied. This is used in bad omen, totems, and the hero of the village to display the floating icon once you get the effect. Duration Number of ticks before the effect wears off. DurationEasy Number of ticks before the effect wears off for Easy mode. DurationNormal Number of ticks before the effect wears off for Normal mode. DurationNormal Number of ticks before the effect wears off for Hard mode. Id Numerical potion Id.   example: 28 ShowParticles Defines if particles are shown or not. FactorCalculationData Unknown usage change_timestamp Unknown factor_current Unknown factor_previous Unknown factor_start Unknown factor_target Unknown had_applied Unknown had_last_tick Unknown padding_duration Unknown auxValue Defines a numerical ID for what arrow type it is, whether it is tipped and with what potion.   example: 23    (Healing II) SelectedInventorySlot Numerical ID of a slot selected in a players inventory. SelectedContainerId Numerical ID of a container selected by the player.  Sleeping Defines if the player is sleeping or not. SleepTimer Defines for how long the player has been sleeping in a bed. SpawnBlockPositionX Defines the X location for the players respawn block like a bed or respawn anchor. SpawnBlockPositionY Defines the Y location for the players respawn block like a bed or respawn anchor. SpawnBlockPositionZ Defines the Z location for the players respawn block like a bed or respawn anchor. SpawnDimension Defines what dimension the player's spawn point is located in. SpawnX Defines the X location for the players respawn point. SpawnY Defines the Y location for the players respawn point. SpawnZ Defines the Z location for the players respawn point. EnchantmentSeed RNG seed for enchantment tables to deterministically give you the same enchantments. RideID Unique numerical ID of an entity that the player is riding. LeftShoulderRiderID Unique numerical ID of an entity that the player has on its left shoulder. RightShoulderRiderID Unique numerical ID of an entity that the player has on its right shoulder. PlayerGameMode Numerical ID of the gamemode the player is in currently. PlayerLevel How many experience levels the player has. PlayerLevelProgress How much experience progress a player has to the next level. Not all NBT tags are used in a standard entity, this just includes all known NBT labels and their known purpose. NBT definitions