I can't figure out how their "skip turn" ability is useful at all. I read the Errata but that didn't help either. Will someone explain how it works and the benefit of their ability as opposed to passing your turn?

During the Action Phase, players take turns executing actions in Initiative order. Player A takes one action, then player B takes an action, etc. Once everyone's taken one action, player A takes a second action, and so on until everyone has "passed." Players must take an action in Initiative order, or else "pass." Furthermore, they cannot "pass" until they have taken their Strategic Action for the turn (ie: used their Strategy Card.)

Once a player has "passed" he cannot take any more actions until the subsquent Action Phase (after scoring points and picking new Strategy Cards.)

Yssaril can "skip" his action for one cycle and then take an action again later in the same Action Phase , which among other things allows him to "wait out" his opponents and then take all his important actions after everyone else has "passed" and cannot respond. It's easily the most powerful ability in the game once you know how to use it.

But Yssaril cannot "skip" twice in a row, so he must take actions at least once every other cycle during the Action Phase.

Ah, ok, makes sense. Thank you.