Mckiller's Mob Expansion

MMM V6.1: changelog

NERFS
-Nerfed the yellow creeper's explosion by 0.7
-Nerfed vampire bleed damage
-Nerfed nether tamer loot
-Nerfed ender creeper movement speed
-Nerfed damage of Ancient Knights
-Nerfed the Vampire's follow range (was 64 is now 32)
-Nerfed vampire's speed by 0.03 (was 0.28 is now 0.25)
-SCRAPPED the charm of piecekeeping (yes I nerfed YOU, YOU are getting NERFED, you can no longer dip out of a fight for free)

BUFFS
-Increased the Sentinel's HP (was 555 is now 650)
-Increased the Sentinel's attack damage by 2 (was 7 is now 9)
-The ice cat can now fight back (full ice cat rework coming at some point)

NEW STUFF
-Updated nether tamer to have a UI instead of just right clicking
-Gave the Gutted a special attack (jump ground slam kinda thing)
-Most advancements now unlock recipes that use that mobs drop
-Added an advancement for encountering a skeletal pigman 
-Changed the icon for the start advancement (not really that important at all but I wanted to log it none the less) 

FIXES
-Fixed advancement related to vampire not being rewarded to the player properly
-Fixed some spelling mistakes
-Fixed multiple Sentinels being able to attack at the same time