A few more things after talking to my friend who also went with last night:
There is an ability that lets a rogue run past his enemies, provoking AoO. The trick is, that they don't hit him...they HAVE to hit themselves!
There is an ability that allows the rogue to jump on the enemies back, and begin to garrote them as a grapple. If they can hold the grapple for 3 rounds, the target falls over unconscious. Additionally, enemies trying to knock him off, have a solid chance of hitting their comrade.
There is an ability that if the rogue hits you when you're bloodied, it does 7[w] damage and crits on a 17+.
All of the above were 15th level abilities.
Humans - Broken again, (they get a bonus at will power from their class, a bonus feat and a bonus skill).
Half elves can take an at will ability from *any* class, and make it an encounter power for them.
Dragon Born's breath weapon scales as they level, capping at like 3d6 or so (again, not bad for a minor action...and not sure how feats could affect this).
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