I play a lot of spell casters. Many of my friends do not like to play the “more difficult” characters. So Clerics, Sorcerers, Wizards, Druids, etc… I get to play a lot. It is very fun because they can do so much.
My favorite spell overall would be Magic Missile. It is an Arcane spell so only Sorcerers and Wizards have access to it. It does 1d4+1 damage per bolt. The number of bolts are based on you level, a max of five bolts.
I know that doesn’t seem like a lot of damage. However the caster does not role to hit, the target does not get a save to resist. Basically the spell does “true” damage. There are a few things that stop it. But with the right feats a Sorcerer or Wizard could prepare it and do max damage with every casting. 5d4+5 = 25 “true” damage.
Currently for my upcoming campaign the party will be facing a Wizard who exploits the full effects of Magic Missile.