Originally Posted by McDungeon
An elf controller will probably want thunderwave and cloud of daggers for their at wills pick. (Though I love ray of frost)
Cloud of daggers is a guaranteed hit vs minions for the +wisdom dmg. And can deter some mobs from charging or whatever else.
It nukes harder than magic missile because of this(assuming 18 wis). 1d6+4+3 potentially, vs 2d4+4 or 5... 10.5 vs 9 or 10 average. Scales even better than magic missile later too. 1d6+6+5 vs 2d4+6 or 7... 14.5 vs 11 or 12 average at paragon tier.
Thunderwave can also benefit from the +wis dmg by potentially knocking enemies into, or through the cloud.
This isn't so useful for the controlling aspect, but, a controller mage has limited options for damage and the +wis is a nice effect, or when you're mopping up at the end of combat.
You can also action pt beforehand to use icy terrain, and make them prone, that way you can push them back with thunderwave into a cloud of daggers and stack up the mobs. The mobs can't shift 1 for occupied sq. due to the difficult terrain to stand up, so as long as one mob is standing on that square, they all dogpile and take the cloud of daggers damage.
That trick synergizes well with orb implement at 1st lvl to 10th, but I still like wand for the +hit and prefer the second implement of orb at 11th.