Changelog

[4.0.0-1.21.1] - 2026-10-06

Fixed

• Mossy Cobblestone portal now can be open with a flint-and-steel to access mining dimension.

[4.0.0-1.21.1] - 2026-10-06 — The 1.21.1 NeoForge port

Changed

• Ported from Forge 1.18.2 to NeoForge 1.21.1 (Java 21).
• Worldgen rewritten from Java code to datapack JSON (configured_feature + placed_feature + neoforge:add_features biome modifiers) — the only way 1.21.1 supports it.
• Every modded ore now carries a mod_loaded condition: missing companion mods are skipped silently instead of crashing. Mods without a 1.21.1 release (Thermal, Vault Hunters, Mythic Botany…) activate automatically if they ever update.
• Heights fixed to absolute Y matching the dimension layers (stone 32–64, deepslate -1–32, netherrack -32–-1, end stone -64–-32). Previously ores generated one full world-depth off and layers came out empty.
• 1.21.1 datapack formats: biome (has_precipitation), dimension types (monster_spawn_light_level + monster_spawn_block_light_limit).

Added

• +39 ores mapped from the modpack scene with original size/rates, remapped to our layers: Create (zinc), Modern Industrialization (10 metals × stone/deepslate), Railcraft, Irons Spellbooks (mithril), Ice and Fire, Oritech, Silent Gear, Theurgy, RFTools shards.
• WORLDGEN.md: guide for pack makers to add/remove ores without code.

Removed

• Ore IDs that no longer exist on 1.21.1: AE2 certus quartz (AE2 19.x dropped quartz ores), Powah dry ice, MA soulstone, Forbidden Arcanus xpetrified, old Occultism silver IDs.
• The 10 per-mod .toml configs and vein/toggle options (JSON is static — numbers are frozen defaults now). Only x/y/z arrival point remains configurable.
• Legacy Java worldgen (~40 classes), BiomeLoadingEvent handler, old mods.toml/ForgeGradle build files.

Fixed

• /mining teleport rewritten for 1.21 API; returns to the exact spot left in the Overworld.
• Mod loading crash from EVENT_BUS.register without listeners; BlockPos double constructor removal; POI, dimension keys, tags and events migrated to NeoForge registries.