Tryndamere's E, Spinning Slash, has a %100 AP Scaling in comparison to +1.2 per every bonus AD. AND. Your Q, Bloodlust, has a heal that heals (At Max Rank) for 70 + %30 of your AP AND 2.3 plus 1.2% of your AP per Fury Healed. That and you're Tryndamere. Mad heals, mad invul's, mad slows, mad gap closers, mad crits, mad money.

Make sure to proc thunderlord's decree before backing out
Try to use your Q only when you're on high fury
Don't miss your E
Don't forget to ult, and try to heal before you ult