Heal and its cooldown.

[Spire]

If priests are so useless at healing, then why do so many people play them as their mains?

You seem to want a priest to have some kind of attack skill to over dominate their opponents, like 'Mega holy light of doom' -(Which can be achived but soul linking the Priest and then using lex Aeterna) Also Priest =/= Tank unless you make it into one. Priest are back row characters in 99% of video games and in my opinion, thats how they will stay. (With the excepting of a few characters in hero of course)