How to Get Blood and Make a Bucket of Blood
Obtaining Blood
Blood is collected with a Bucket of Blood. To fill a bucket, you need a source of blood in the world. Kill mobs that drop the mod's flesh and organ materials and collect the resulting drops, then process them toward blood collection. The Bucket of Blood is the container item you end up holding once blood has been gathered.
Using Blood
Once you have a Bucket of Blood, it is a crafting ingredient for the mod's flesh and organ blocks and for higher-tier gear. Blood feeds into recipes for Block of Flesh, Block of Hearts, Block of Muscles, and Block of Ribs, which are the base building blocks of the mod's progression. Keep a steady supply: many later recipes consume these blocks, so stockpile Buckets of Blood before you start crafting tools.
Practical Loop
1. Gather flesh and organ drops from mobs.
2. Convert drops into blood using your bucket.
3. Craft the base blocks (Block of Flesh, Block of Hearts, Block of Muscles, Block of Ribs).
4. Use those blocks to unlock the §6 tier items such as §6Flesh Carcass and §6Blazing Heart.
Blood is the entry point for everything else in the mod, so treat it as your first resource bottleneck.