I think it's biggest issue is the wording of the trigger. I could see potential combinations with gas based spells and grappling builds otherwise that could lend it some interesting functionality. However, I think if a party really did want to do that a caster could just position their gas spell in such a way that a grappler could hold a target in place without occupying the affected area.
I think if it just lost that second sentence, that would go at least some of the way towards making it better.
Situational but not terrible. More a spell for a wizard than other classes and not a terrible one for a staff. I'd rule it that it negates breathed in poisons etc. Which I think is the intent and makes this much stronger. Your GM might rule differently.
I think it's biggest issue is the wording of the trigger. I could see potential combinations with gas based spells and grappling builds otherwise that could lend it some interesting functionality. However, I think if a party really did want to do that a caster could just position their gas spell in such a way that a grappler could hold a target in place without occupying the affected area. I think if it just lost that second sentence, that would go at least some of the way towards making it better.
Situational but not terrible. More a spell for a wizard than other classes and not a terrible one for a staff. I'd rule it that it negates breathed in poisons etc. Which I think is the intent and makes this much stronger. Your GM might rule differently.
Doesn't really last long enough to do much with.