While testing my own mod Oceanic Expanse in a personal modpack, I noticed an excessive number of one entity from my mod, the Drowned, spawning. And I do mean excessive, quickly climbing to the hundreds in minutes.

Process of elimination and individual testing found RandomTweaks was the cause. I am not certain why this is exactly, as my Drowned are spawned like any other EnumCreatureType.WATER_CREATURE, and therefore should be subject to all normal spawning rules.