1. Textures

All new blocks, items, entities, etc. will automatically receive classic style texture

2. Music

New biomes will receive music by C418 that best suits it. If the third Minecraft volume were to be released in the future, the music from the volume will be added in the pack.

3. Block Sounds

New blocks will receive their classic sounds. New blocks will retain their vanilla sounds if any of the classic block sounds don't fit well with the block

4. Random Block Rotation

Before Java Edition 1.8, blocks didn't have random texture rotations, so rotation will be disabled for new blocks as well.

5. Spawn Egg Names

All future mob spawn eggs will use the format "Spawn [Entity]"

6. Sky and Fog Colour

All future overworld biomes will have their sky and fog colours picked depending on their temperature and downfall values

7. Underwater Fog

All future biomes will receive the blue underwater fog colour

8. Water Surface Colour

All future biomes will use the pre-1.13 colours.

9. Rarity

Items that existed before 1.21.30 (except trident and smithing templates) will use their rarity prior to that version. If an item that existed before 1.21.30 have its rarity changed, it will be reverted in the pack. All future items will have their rarity stay as is, with some exception:
  -All future music discs will use the pre-1.21.30 rarity (rare)
  -All future pottery shards will use the pre-1.21.30 rarity (common)
  -All future operator utility blocks and items will use the epic rarity

10. Colours

All future tinted blocks and items (can be dyed) will use pre-1.12 colours. Hard-coded colours will stay as is.

11. Pottery Sherd Naming

All future pottery sherds will use the format "[Type] Pottery Shard"

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If the combat test snapshots makes its way to Bedrock Edition, the following will be changed:
1. Rename Cleaving enchantment to "Chopping"