Can you make an opportunity attack against an ally?

[James McMurray]

You decide who your enemies and allies are. If it makes sense to OA a party member, it's probably because they're currently an enemy of some sort, so go for it.

Unless it turns into a bag of rats, of course. But that's covered by another rule.

 

[keterys]

Yeah, tripping up dominated allies (ie, fighter with improvised weapon OAing) seems legitimate to me.

And hey, there's an optimal use for sure strike with heavy blade opportunity

 

[Majushi]

I thought other members of a player group are always considered to be allies. Because otherwise you'd have twats running about changing their allegiance every five seconds to backstab other members and steal their stuff cause they're "teh leet".

 

[James McMurray]

I thought other members of a player group are always considered to be allies. Because otherwise you'd have twats running about changing their allegiance every five seconds to backstab other members and steal their stuff cause they're "teh leet".

The rules aren't that exact. They're there to differentiate between targettable groups, not police peoples' game session in a neverending fight against twats.

 

[Jhaelen]

You decide who your enemies and allies are. If it makes sense to OA a party member, it's probably because they're currently an enemy of some sort, so go for it.

This.

Unless it turns into a bag of rats, of course. But that's covered by another rule.

And this.

Ever had npc enemies infiltrating the party? They don't suddenly become unattackable for all eternity just because there once upon a time you've considered them your allies. Ditto for pcs going berzerk.
Common sense (aka bag of rats) will make sure the rule cannot be abused by a player trying (and failing) to be clever.

 

[Jack99]

When and how do you know if an ally is dominated? Obviously, if they attack, but if they just move?

Typically there is going to be some sort of physical manifestation of the power an enemy uses. It might not be visual, but it might be.

At that point, you're clearly in the realm of DM discretion. But i would argue that a number of powers seem to indicate that intelligent creatures are aware of what status effects are inflicted on their enemies and allies RAI[the ones with reaction/interrupt triggers such as "when a creature inflicts an ally with an effect a save can end..."]

At the very least the player can claim he is entitled to a perception check or intelligence check(why is the wizard walking towards the demons of his own free will!?!?!) to notice the effect with a pretty strong case.

Its actually an insight check DC 25 + ½ effect's level

 

[mach1.9pants]

The rules aren't that exact. They're there to differentiate between targettable groups, not police peoples' game session in a neverending fight against twats.

Hahahahahahaaaaaaaaaa I have just found a new sig!

And use common sense, I would allow OAs against a dominated ally and I would also allow the cleric to give him a bonus to saves.

 

[yesnomu]

Its actually an insight check DC 25 + ½ effect's level

Eh, that's really for noticing if the Emperor's acting strangely at dinner. If you see an enemy's eyes light red, and your buddy turn around and start running at the wizard, I'd let you waive the check.

You can always decide someone isn't your ally--it's reciprocal, both creatures have to agree. This stops dickish Bards from moving everyone around.