Lol today I was going through Zombie Island of Dr.Ned with my Hunter melee build.
I hit 99,999 damage on the regular.
Items were : 200% melee damage athena's wisdom, truxican wrestler class mod (+4 lethal strike 78% melee damage, 48% health and some other thing I don't care about), and 5/5 lethal strike, deadly, and the rest I stuck into bloodwing/random stuff.
It was so lulzy to go around hitting lvl67 zombies for 99k.
However when I tried to kill Pumpkin Jack it went down to 347 damage
I had 340% bonus melee with 900% bonus on the lethals.