Zim for defence, definitely, and the cleanse is especially useful against all the DoT heroes, telly, JF, Clarissa etc.
That being said, Tyr is my favourite hero and wins fights I have no business winning.
No other hero I know can go toe to toe with three other healthy 5* and beat them over 10+ turns.
He’s good as well if you like heal-3 heroes because you can put him out on a limb and he looks after himself.
You’re in a win-win situation 