Updated 25 October 2026. Facts on this page come from minecraft.wiki, community sites named in the text and the live Artemis PvP server; sources are listed at the bottom.
Mob Grinders and Mob Stacking in Factions
A factions grinder is a room of spawners whose mobs are killed for XP and loot to sell. Some servers, like CosmicPE, stack spawner mobs into one mob per type per chunk to save lag, so a big farm becomes a single mob with a huge count. Grinders make money, which is why they sit in the base and why raiders aim for them.
How does mob stacking work?
The CosmicPE wiki describes it on that server: spawner mobs stack within a chunk by type, so there is one stack of zombies, one of blazes and so on. Killing one lowers the stack by 1 and another takes its place; extra damage carries over to the next mob, so one hit can clear more than one. A stack keeps growing to a cap, and stacks of 64 or more do not despawn on chunk reloads. Spawner mobs there are mostly immobile and ignore water and knockback, but drop XP only from melee damage.
Why do servers stack mobs?
Thousands of separate mobs would lag the server and clients. Stacking keeps the output of many mobs while the game only handles a few entities. See mob farms for vanilla farm designs.
How do grinders make money?
Mobs drop items you sell and XP. The CosmicPE wiki says spawner mobs vary in XP, drops, sell price and health. The CosmicPE wiki calls spawners the main way to grind money overnight with automated death traps.
Why are grinders raid targets?
Spawners hold a faction's value and points, and the grinder room is where they are. Defenders wall them in, but many servers require spawners to stay raidable; see factions server rules and spawners in factions.
How do grinders work on ArtemisPvP?
Mobs from spawners merge into one stacked mob per chunk so big farms stay smooth, and you spam-click it to kill the stack. Spawners stack up to 10 in one block and only run inside your claim. The Mob Grinder custom block auto-kills nearby mobs with an inserted sword and stores XP as bottles. See Spawners and Custom Blocks.
Frequently asked questions
What is mob stacking?
On servers like CosmicPE and ArtemisPvP, merging many spawner mobs of one type in a chunk into a single mob with a count, to save lag.
Why do factions build grinders?
To turn spawner mobs into XP and loot to sell.
Sources
Every fact on this page was checked against these pages; the wording is ours.