Smoke Flash grants the targeted pet a temporary buff causing criticals for the duration of the power (10 secs), plus stealth and placate.
For powers like these, it is actually a power granting a temporary power of its own. Check to see if 'smoke bomb' is listed, and then check it. Here is the City of Data link for you.
Does smoke flash give your ninja a power that they use occasionally like the train powers or is it just a one time use thing? The guides seem to suggest one time use but don't specifically say if it is or isn't. I looked at the power and it says it grants smoke bomb to genin (much like the train powers say they grant a power). So I'm a bit confused.