New Gamerule: /MobLightReq

As of 1.18.Experimental-1 there was a change with Mob spawning (Hostile in this case). This is bringing some discussions about the future of Mob Spawning.

MobLightReq could be used for maps, worlds, and datapacks that can change minimum and maximum requirements for Passive, Neutral, and Hostile mobs! 

Ex /Gamerule MobLightReq Passive 11 15

This also gives players an option to tinker with mobspawnings and find potential bugs that were either overlooked, or may have been previously undiscovered!