I have heard that you can cancel your own powers/abilities and team abilities, is this true and if so how long are they canceled for?

Under the current rulebook, this is correct.

If they are not marked as "non-optional" they are optional and can be canceled until the end of the current turn.

Until May 1. (There is a rules change coming, but we don't know exactly how things will work.)

At the moment, powers/abilities are optional unless indicated otherwise. That means you can cancel them in response to an action. Powers remain canceled until the beginning of the next player's turn.

From p. 15 of the 2010 Core Rulebook:
From p. 15 of the 2010 Core Rulebook:

Yes, unless they are "non-optional'.

They are canceled until the end of the current players' turn.



EDIT* Dang, Harpua beat me!

ok ty everyone!