Flaxian Assassin
by Kathy McCracken

This dilemma filters out, not a specific skill, but one of your opponent's better personnel--someone with three or more skill dots. The requirements to pass it are pretty stiff, too. Most people will routinely include one SECURITY in any non-redshirt Away Team, but they're less likely to have two, and Biology just isn't that common. Since it has conditions, but no "discard dilemma" clause, it will go back under the mission even if the Flaxian finds no target to eliminate. And to put the icing on the cake, you only have to have Tal Shiar skill in play (not present at the mission site) to kill off two personnel instead of one.

Combo:
Hippocratic Oath + Flaxian Assassin: Most biologists are MEDICAL personnel, so you have a good chance of getting rid of two good personnel.