This add-on buffs all mobs hostile and passive. This add-on will put a challenge on any Minecraft player. Even cows will ram you if you get too close. Most mobs have way more health and do way more damage. Bats will attack you now too. All in all this add-on will make a veteran player feel like a derp/noob.
Wither Skeletons now have about twice the health and do twice as much damage.
Strays will no longer burn in the sun and will shoot at you from a mile away. Plus strays and skeletons have a higher fire rate and range.
Beware of cows because if you get too close (2 block radius) they will ram you and do 7 damage.
Skeleton horses, horses, zombie horses, mules and donkeys all are faster, bigger and have more health