RLCraft server setup on Hostd: tier, Lycanites, and 1.12.2 quirks

RLCraft is a 1.12.2 Forge survival overhaul. Heavy tier minimum, the Lycanites mob cap is the big lever, and the vanilla difficulty flag does not apply.

The short version

RLCraft is a Forge survival overhaul on Minecraft 1.12.2. Take the Heavy tier at 10 GB, install the pack from the Modpack tab, and let first boot finish. The Lycanites mob cap is the single biggest performance lever, and the vanilla difficulty setting in server.properties does not control RLCraft's difficulty.

RLCraft is a hardcore survival overhaul on Minecraft 1.12.2 Forge. Everything wants to kill you, the dragons are real, and the server side is older and crankier than a modern 1.20+ pack. Hostd installs RLCraft cleanly; the gotchas worth knowing are mostly about the tier and the Lycanites mod.

#Pick the right tier

RLCraft needs the 10 GB plan at minimum. Java 8 is the supported runtime (we set this automatically; do not change it). With 2 to 4 players exploring the world, expect to use 6 to 8 GB of heap. With 6+, move to the 14 GB plan. the 6 GB plan will boot the pack but will not survive a populated overworld at night.

#Installing the pack

At order time: on the Minecraft Java Configure page, toggle Modded and pick RLCraft from the modpack browser. Provisioning includes the full pack download and config.

On an existing server: Dashboard → your server → Modpack → search "RLCraft" → Install. Take a backup first if you have anything you want to keep (Taking a manual backup).

#First boot

First boot is 6 to 12 minutes; 1.12.2 Forge is slower to load than 1.21. You will see Lycanites print a wall of registration messages; that is normal. When the console says "Done", you can connect.

#server.properties tweaks worth doing

Open Files → /data/server.properties and check:

  • view-distance=6. Default is 8 to 10; drop to 6 (or 5 on a small group). RLCraft worldgen is dense and view distance is the single biggest TPS lever.
  • max-tick-time=-1. Disable the watchdog. RLCraft worldgen can spike a single tick over the default 60-second limit during a dragon spawn or a Lycanite event horde and crash the server on its own watchdog. Set to -1 to disable.
  • spawn-protection=0. RLCraft is not the kind of server where spawn camping is the problem; remove the protection so structures place properly.

#Lycanites mob cap

Lycanites Mobs is responsible for half the difficulty and most of the lag. It has its own mob cap independent of the vanilla one. Open Files → /data/config/lycanitesmobs/global.cfg and find:

mob_limit=

The pack default is high. Drop it to 20 to 30 per player for a small group. Restart to apply.

#Difficulty

RLCraft does not respect the vanilla difficulty flag; the pack hard-sets hard mode. Players will die in their first night to a temperature crash or a roc swooping out of the sky. That is the pack working as intended.

#Where to go next

#Frequently asked questions

How much RAM does an RLCraft server need?

10 GB. RLCraft is a 1.12.2 pack, and 1.12.2 handles memory less efficiently than modern versions, so the usual advice about lighter packs does not transfer. Below 10 GB you will meet heap errors during mob-heavy nights.

Why is my RLCraft server lagging at night?

Lycanites mob spawns. The pack spawns a great deal more hostile mobs than vanilla, and the default caps assume a singleplayer world. Lowering the Lycanites mob cap in its config is the single most effective change you can make.

Why does changing difficulty in server.properties do nothing in RLCraft?

RLCraft manages its own difficulty through pack configs rather than the vanilla difficulty flag. Setting difficulty=hard in server.properties changes vanilla mob behaviour but leaves the pack's own systems where they were.

Written and maintained by the Hostd engineering team. Last updated 2026-05-23. Notice a mistake? Tell us.

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