Versatile Master

Paragon Tier
Prerequisite: 11th level, half-elf
Benefit: You can use the power you chose through your Dilettante racial trait as an at-will power.
    If you choose the paragon multiclassing option, you can choose powers at 11th level, 12th level, and 20th level from any class, instead of only from your second class. You can also spend an action point to regain the use of an encounter attack power that you have already used during this encounter, instead of taking an extra action.

Published in Player's Handbook 2, page(s) 193.