Elder Guardian

The Elder Guardian is a mob added by vanilla Minecraft. They are stronger and larger variants of Guardians. Three Elder Guardians spawn in every ocean monument structure and will not despawn naturally, although Peaceful difficulty will still despawn them as normal. There is no way to respawn them, so there are a limited number of Elder Guardians per world.

Advent of Ascension does not alter the Elder Guardian. However, it does add extra rewards for defeating it. The rewards are displayed below. Full information on this mob is available on the Minecraft Wiki, although some information on there may have changed between the Minecraft version Advent of Ascension is currently on and the latest Minecraft version.

Elder Guardian Loot Table
When the Elder Guardian is killed, it will drop items from the below loot table in addition to its other drops.

Note: in versions of the mod for Minecraft 1.15.2, this loot table is not rolled due to a bug. As such, Biogenic Armor is unobtainable in those versions.