Bad Omen should enable more events

I would love to see Bad omen get more uses beyond trial chambers and raids. i wish that it would allow for mobs to spawn when they normally wouldn't. i can imagine phantoms spawning regardless of insomnia level and Guardians spawning from a fishing rod event, Maybe even Elder Guardians at bad omen V. 

While the phantoms wouldn't see much use, The guardians would allow players to get access to prismarine in challenge worlds that previously wouldn't. Like superflat and skyblock. If Elder guardians were allowed too, it would add a renewable, yet cumbersome, way to get sponges.