Planeswalker question???

[ibtrickey]

I wanted to know if an opponent casts  {Xenagos, the Reveler} can they use the zero ability right after?
I thought you had to wait a turn

[Rass]

Yes they can.

[ibtrickey]

306.5d: Each planeswalker has a number of loyalty abilities, which are activated abilities with loyalty symbols in their costs. Loyalty abilities follow special rules: A player may activate a loyalty ability of a permanent he or she controls any time he or she has priority and the stack is empty during a main phase of his or her turn, but only if none of that permanent's loyalty abilities have been activated that turn. See rule 606, "Loyalty Abilities."

[ibtrickey]

Would not the stack be not empty until the next step? So I thought they could not use it in that main step

[Sardok]

Would not the stack be not empty until the next step? So I thought they could not use it in that main step

This just means they follow the same rules as sorcery speed abilities. Once they resolve the stack becomes empty anyway.

[ibtrickey]

But I thought the stack only empties on a new step?

[Sardok]

But I thought the stack only empties on a new step?

The stack is empty when nothing is on it. You can only go on to the next step when the stack is empty, not the other way round.

[ibtrickey]

Okay

[Ekann1]

No. He has summoning sickness, even though he isn't a creature.
1/24/2013   If Gideon, Champion of Justice becomes a creature the same turn he enters the battlefield, you can't attack with him or use any of his {T} abilities (if he gains any).