Legacy Version 1.12

Mob Settings started as a mod for customizing vanilla mobs using individual Forge configuration sections, with support for custom drops, spawn biomes, group sizes and spawn weights.

For example, the original Bat configuration looked like this:

bat {
    I:batAmountMobDrops <
        1
        3
        0
    >

    S:batMobDrops <
        minecraft:dirt
        minecraft:rotten_flesh
        minecraft:stone
    >
}