Mob Stacker Ind. Mod für Minecraft 1.20.1, 1.21.5

MobStacker is a performance Minecraft mod to optimize entity handling, addressing a common cause of performance issues in vanilla and modded environments. By intelligently "stacking" similar mobs in close proximity, MobStacker significantly reduces server load and enhances client-side performance without compromising gameplay mechanics.

Requires: Dungeon Config and Fabric API. MobStacker is server side only: players don't need it installed to join.

Note: MobStacker preserves all loot and mob properties within stacked entities. Named mobs (via name tags) are exempt from stacking to maintain uniqueness.

Key Benefits

• Server Performance Boost: Dramatically reduces entity processing overhead.
• Enhanced Client FPS: Lowers strain on client-side rendering.
• Optimized Network Traffic: Minimizes entity data transmission.
• Cleaner Gameplay: Reduces visual clutter in mob-dense areas.
• Memory Usage Reduction: Lowers overall memory footprint.

Performance Improvement

While actual performance gains vary based on server specifications, player count, and mod configurations, MobStacker can provide substantial improvements, especially in environments with:

• High mob density
• Numerous entity-adding mods
• Large, active player bases

🔗 Note:

• MobStacker has a built in configurable spawn cap module to reduce mob spawns per chunk.

Features

Feature Description

Smart Stacking Automatically combines identical mob types within a configurable radius

Strict Matching Only stacks mobs whose visible variant and saved data match, including data added by other mods (elite affixes, levels, owners…)

Customizable Stacks Set preferred maximum stack sizes, globally or per rule

Flexible Health Management Configurable options for stack health, death mechanics and batch kills

Multiplied Drops Shearing, brushing and natural drops (eggs, scutes…) scale with the stack size

Batch Breeding Breed several mobs of a stack with one feeding

Stack Combat Optionally multiply a stack's melee damage by its size

Selective Stacking Exclude specific entities, entity tags or entire mods

Rules Change any setting for specific mobs, dimensions, biomes, chunks or areas

Claim Support Players can make rules for their own claims (FTB Chunks, Open Parties and Claims)

Stack Splitting Separator item splits a mob off a stack; assimilator item toggles whether a mob can stack

Stack Names Per-player localized stack labels (e.g. "Zombie x5") that are never saved onto the mob

In-game Config Every option is editable from the Dungeon Config settings screen

What Never Stacks

To keep gameplay intact, MobStacker leaves these mobs alone:

• Babies, mobs with no AI and mobs with a custom name
• Riding, ridden or leashed mobs, saddled mobs and mobs wearing body armor
• Tamed or owned mobs, horses and their relatives, and mobs released from a bucket
• Mobs carrying items, animals in love mode and player-built iron golems
• Raiders in an active raid and patrol leaders
• Villagers with a job, bed or meeting point (jobless villagers and nitwits can stack; a villager leaves its stack the moment it claims a workstation or bed, so trading halls, breeders and iron farms keep working)
• Mobs holding equipment that is guaranteed to drop
• Bosses (anything in #c:bosses or with at least bossHealthThreshold base health), unless stackBosses is on
• Anything in the #mobstacker:unstackable entity type tag, which by default includes the Ender Dragon, Wither, Warden, Elder Guardian, Wandering Trader, Allay, Bee, Vex, Happy Ghast, Copper Golem and Creaking

Configuration

The config lives at config/mobstacker/mobstacker.json5 and can also be edited in-game from the Dungeon Config screen. Old mobstacker.json configs (including mob groups and chunk overrides) are imported automatically on first launch.

Stacking

Option Description Default

maxMobStackSize Maximum number of mobs in a single stack (1 - 4096) 16

stackRadius Radius in blocks within which mobs attempt to stack 6.0

stackCheckInterval How often, in ticks, each mob looks for a stack to join 20

strictDataComparison Only stack mobs whose saved data also matches, including modded data true

matchSoundVariants Also require pigs, cows, chickens, wolves and cats to sound the same false

Death & Loot

Option Description Default

killWholeStackOnDeath Kill the whole stack at once, dropping loot and XP for every mob false

killBatchSize How many mobs die per kill when the whole stack doesn't die. Loot is multiplied to match 1

stackHealth Combines health of stacked mobs; the stack is worn down as a whole. Implies killWholeStackOnDeath false

multiplyShearDrops Shearing or brushing a stack does it to every mob and multiplies the drops true

scaleToolDamage Shears and brushes used on a stack wear down as if used on every mob true

damageWeaponPerHit When a stack dies as a whole, each hit wears the weapon down for every mob in it false

multiplyGiftDrops Multiply drops a mob produces on its own (chicken eggs, armadillo scutes…) true

instantKillWholeStack /kill and falling out of the world remove the whole stack true

Breeding

Option Description Default

breedBatchSize How many mobs of a stack can be bred with one feeding. 1 keeps vanilla breeding 1

breedCooldown Ticks before a stack can be batch bred again 6000

Combat

Option Description Default

stackOutgoingDamage Multiply a stack's melee damage by its size false

maxDamageMultiplier The largest damage multiplier stackOutgoingDamage can apply 16

Items

Option Description Default

enableSeparator Right-clicking a stack with the separator splits one mob off (the split mob won't stack again) false

consumeSeparator Determines if separator item is consumed (or damaged) on use true

separatorItem Specifies the item used as a separator "minecraft:diamond"

enableAssimilator Right-clicking a mob with the assimilator toggles whether it can stack false

consumeAssimilator Determines if assimilator item is consumed (or damaged) on use true

assimilatorItem Specifies the item used as an assimilator "minecraft:emerald"

Display

Option Description Default

showStackNames Show the stack size above stacked mobs. Only sent to players, never saved on the mob true

alwaysShowStackNames Show the stack size at all times, not only when looking at the mob false

stackNameFormat Label format. {name} is the mob's name in each player's language, {count} the stack size "{name} x{count}"

Filters

Option Description Default

ignoredEntities List of entities excluded from stacking ["minecraft:ender_dragon", "minecraft:vex"]

ignoredMods List of mod IDs whose entities are excluded from stacking ["corpse", "cobblemon"]

stackVillagers Let jobless villagers and nitwits stack true

stackBosses Allow bosses to stack false

bossHealthThreshold Untagged mobs with at least this much base max health count as bosses. 0 turns this off 150.0

Mob Caps

Option Description Default

enableMobCapOverrides Replace the vanilla per-category mob caps with the values below true

monsterMobCap Monsters (vanilla 70) 25

creatureMobCap Animals (vanilla 10) 5

ambientMobCap Bats (vanilla 15) 7

axolotlsMobCap Axolotls (vanilla 5) 2

undergroundWaterCreatureMobCap Glow squid (vanilla 5) 2

waterCreatureMobCap Squid and dolphins (vanilla 5) 2

waterAmbientMobCap Fish (vanilla 20) 8

Rules & Claims

Option Description Default

claimRules Let non-operators make rules for chunks they or their team have claimed true

maxRulesPerTeam How many rules one player or team can own 10

playerRules.<setting> Which settings players may change in rules for their own claims Stacking, max stack size, data/sound matching, stack names and villager stacking

Rules

Rules change settings for some mobs or some places, like a bigger stack size in your mob farm or no stacking at all in a boss arena. A rule can match:

• Mobs: ids like minecraft:zombie, tags like #minecraft:undead, or a whole mod like @alexsmobs (empty = every mob)
• Dimensions: like minecraft:the_nether (empty = all)
• Biomes: ids like minecraft:plains or tags like #minecraft:is_ocean (empty = all)
• Places: chunks or block areas, e.g. minecraft:overworld 0 0 63 63 (empty = everywhere)

Inside a rule every setting from the sections above (except filters for mods/entities, mob caps and the check interval) can be overridden or left on Global, and stacking itself can be switched off. When several rules match a mob, the one listed first wins. Rules are saved per world in serverconfig/mobstacker-rules.json.

With FTB Chunks (with FTB Teams) or Open Parties and Claims installed, players who aren't operators can create rules too. Their rules only apply inside chunks their team has claimed, and they can only change the settings the server allows.

Commands

All commands are prefixed with /mobstacker. Everything except /mobstacker rule requires operator permissions (level 2).