Magistrate, I believe that would be a Linked Test. I liked Linked Tests! But remember, before your player picks up dice to make a roll, they need to declare Intent and Task - and they have to be reasonable relative to what the character knows/would do.
So before the player character is aware of the assassin - even if the player is aware of the assassin - is, I believe, an inappropriate time to kick off a linked test.
But, at the point at which the assassin kicks in the door, poisoned dagger held menacingly in hand, the player can declare an intent and task that can be resolved by a linked test. Here’s some possibilities:
A)
The Intent is “I want to keep Roger from getting hit by the dagger! I shove him below the table”
Could be resolved by a single test to shove Roger down below the table, or more complicated,
B)
The intent is “I want to protect Roger! I kick his chair out from under him and throw my mug at the assassin to distract him”
Could be resolved by a linked test, first Power to kick out the chair and then maybe Thrown Weapon to aim the mug right. At the end of the linked test you know the cumulative result of your efforts to keep Roger from getting stuck with the wrong end of the dagger.
C)
The intent is “I nee to get Roger out of this tavern and to safety! First I need to slow down the Assassin, then I need to get him out of the tavern, then I need to find a place to hide.”
Could be resolved by a linked test, first maybe Thrown Weapon again to toss a mug in the Assassin’s face, then Speed (perhaps at a penalty if Roger is slow), then Inconspicuous or whatever is appropriate.
I think that Linked Tests are a great way for player and GM to collaborate on the direction the story takes. At first pass, we’ve got a relatively static situation. It’s do or die right here in the tavern. Will Roger take a poisoned dagger to the chest right now or will he not? But the player could take that scenario and turn it into a chase scene, or an all-out tavern brawl, depending on how they declare their Intent and Task. Roger could end up poisoned either way. The narration after the fact, if you go the escape route but fail in the end, could be that Roger takes a hit from the poisoned dagger on the way out, but you end up escaping anyways, and now you’re trying to find a way to heal the poisoned wound while the assassin is still at large… Or maybe you get away scott free, but end up in bigger trouble because you flee headlong into a vicious gang’s territory…