Optifine changes mob spawns and it was found out recently, if you have a potato pc use sodium by jellysquid it boosts frames more but has less options.
From my understanding, you cannot use Optifine because it affects mob spawning. You can use other mods like Sodium or Phosphor that boost performance also, as an alternative to Optifine. Look in the rules and resources, you can find the info you need.
mob spawning is just ONE of the many reasons. One of the others is the fog. Unlike vanilla, Optifine provides a HUGE advantage to fog distance especially in the nether
@rewan Optifine fog even turned on still gives a huge advantage over Vanilla fog as it's much less than it should be
@rewan basically fast fog is such a huge advantage. Only fancy fog makes it vanilla-like, but some PCs cant handle it bc of graphics cards and whatnot
