Why exactly is he disgusting? Is it due to metamorphosis?
it's due to him being pretty much #1 in every carry category
insane push? check
ranged illusions that deal over 100% of his melee base damage? check
Unconventionally low BAT? Check
survivability/mobility? check thanks to base stats
Unconventionally high regen? check
Hands down best slow in the entire game that can be left at level 1 and is unpurge-able? check
high damage? check
early game? check
mid-game? check
late-game? check
check
check
check
no mana problems whatsoever? check
check
Only two drawbacks: moderately high cast time and short range on sunder/reflection, but those aren't nearly enough considering his strengths.
Now normally you'd look at this list and be like shit this looks like a standard melee hard carry with high base stats and certain strengths to off-set the fact that melee carries are kited pretty easily in the late game. Welp, TB doesn't really suffer from that problem with an on-demand ranged form and all that also exponentially increases his damage output.