Going to a regional today, got single purpose and was wondering if I can use it for a special action on a card like grenadier. Where is the info on timing for command cards played ? Thanks

Yes, an ability with A is a special action and can be performed up to twice per activation if Single Purpose was played on that figure (cards with restriction box are played on a single friendly figure) at the start of that figure's activation.

You play a card when specified in the ability. If multiple abilities trigger at the same time, they are played and resolved in the timing conflict resolution order (p.2. of RRG). When to play attack-related cards (and other attack info) see Ability Resolution Order during attacks.

But when I play a card like grenadier, does it stay available for the whole turn, or does it stay only for the action ?

15 minutes ago, Viperhook said:

But when I play a card like grenadier, does it stay available for the whole turn, or does it stay only for the action ?

Not sure I understand the question. You have to perform the grenadier action when you play the card. It’s a one-time use.

-ryanjamal

28 minutes ago, ryanjamal said:

Not sure I understand the question. You have to perform the grenadier action when you play the card. It’s a one-time use.

-ryanjamal

What if I play single purpose at the start of my activation, can I use it twice. That's what I mean, where is the duration of a card written in the rulebook. Some command cards last more than one turn, some one turn, etc...

You would need another Grenadier to use it a second time. (But you can only have one in your deck, so you would need some command deck shenanigans.)

Some command cards give lasting effects, but they always define that effect and its duration explicitly.

Single purpose is great for stuff like focusing with c3po twice or force choking twice with Vader for instance.

It will be useful in my squad, just wanted to know if it could be extra useful