Mannahnin
Scion of Murgen (He/Him)
IIRC my first 4e character used that trick.I think it was “Knights of Last Call” that pointed out a half-elf fighter can use the dilettante feature to pick “scorching burst”, toss that out in a battle against some clumped enemies, and mark all of them.
Basically, giving allies a +2 bonus to all defenses against attacks from those enemies.