"More Mobs"

Tons of new monsters to fight, neutral creatures to farm and items to collect.

Y=59 and below now contains new enemies - the Miner and the Cavecreep.
Cyclops is a new neutral mob that spawns in all biomes where you can meet most passive mobs.
The Martyr and Wither Skeleton Horse are very hard to find.
If you thought Ender Sentinels were bad enough, Ender Phantoms will begin to spawn once you've defeated the Dragon.
The End Barrens now contain new hostile and neutral mobs for you to farm.
Demons replace Skeletons in the Nether. This new powerful foe will give you a run for your money.
Aside from peaceful Scoopers the Nether is now filled with new dangerous mobs, such as the Nether Spider.
Illusioners, aside from appearing in Pillager outposts, join raids now. Sometimes riding Ravagers.