I'm giving Inktober a shot this year, using a D&D themed prompt list! Almost done; just one day left!
Day 30 is "Your Favorite Spell/Ability." There are so many favorites of mine, be they super powerful spells like Meteor Swarm (A.K.A. BBEG Crowd Control), to Legendary Resistances, etc.
My favorite though has to be the Divine Smite option on paladins. A bunch of extra damage that you can add to an attack after the result of the dice is seen? And it doubles on a crit!? Sign me the fuck up!