There is one in Dream mastery that doesn't need any target: Distort Reality.
A very efficient skill if by gear or skills you can raise up physical damage.
Other skills without target needed iirc:
- Thunder strike (rune)
- Poison bomb (rogue)
- Volcanic orb, Flame surge, Eruption (earth)
Note that if you play melee you don't really need to target a special monster: aggro a group of monsters, and just left click on your attack skill. This way you will automatically hit each monster around you. With the help of passive skills like the shield tree in defence or the DW tree in warfare, this looks like an AOE skill. I don't know if it's possible on Xbox though.