Mobzilla (based on Toho's Godzilla) is the strongest hostile mob in Minecraft, added in the 50.6 update. It only spawns in Ocean and Plains biomes and is not manually summoned. Its arrival is always marked with a massive storm 10x more dangerous than typical ones. Also, for good measure, around 50 Iron Armor Zombies are following him at all times, fending off any players. He stands at over 50 blocks high, towering over any other entities.
Damage Value: 10 Hearts per kick.
Kick/Punch - Standard melee attack, temporarily displaces target 2 blocks in the air.
Atomic Breath - Launches a barrage of dozens of Ghast and Blaze bombs.
Lightning - All players within the immediate vicinity of Mobzilla will periodically be hit with lightning bolts.
Seismic Attack - Tosses all nearby players 10 blocks into the air.
Lava Breath - Spews lava source blocks in all directions.
Roar - Gives all nearby players a Weakness and Slowness status effect for 20 seconds.
Nuclear Pulse - Sets all nearby players alight until in contact with water
No fire damage
No fall damage
Moves extremely fast in water
Sinks to the bottom of water masses
Destroys terrain in its way
Destroys layers of player-made blocks when stepped on
Super Regenerative Powers (2 hearts per second)
Self destructs on death, killing everything around it (10 second warning marked by glowing, roaring, and explosion particles)
Becomes stronger when in contact with water or lightning
Drops on Death
64 Mobzilla Hide - Used to craft strongest armor in the game
2-5 Mobzilla Claw - Used to craft strongest sword and bow in the game
128 Mobzilla Tooth - Substitutes as 10x more powerful arrows for bows (compatible with Infinity)
4-6 Mobzilla Dorsal Fin - can be combined with any armor piece to add Thorns V enchantment (does not accelerate breaking rate)
25% chance to drop Mobzilla Skull Trophy
Several various Enchanted Books