Blumbo

Reduces randomness in bow and crossbow damage.

Allows you to change explosion power, fire spread and disable dropped item destruction for different explosion types.

Makes Crystal PvP less ping dependant by making End Crystals more client-sided.

Different armor and damage mechanics that make make survival more suitable for PvP.

A bunch of features that make fire more tolerable in Minecraft.

Gives you control over which types of items to keep and which to drop when a player dies.

Makes it easier to get the most out of splash potions.