Tarn Mison's ability states "when an enemy ship declares you as the target of an attack, you may acquire a target lock on that ship."

If I am reading the flow chart correctly that is step 1iii and then M9-G8'8's ability to modify the attacker's red dice is at step 3ii so he should be able to force that attacker to re-roll one of the incoming red die with the target lock acquired in that shot.

Sound right?

Yup that's legit. R7 Astromech is probably a better choice for Tarn though.

1 hour ago, thespaceinvader said:

Yup that's legit. R7 Astromech is probably a better choice for Tarn though.

That's how I was running him, but M9 can give an early "predator" to a friendly ship early game. At least that's my rationale.

Besides, r7 is once per round, m9 is not

3 hours ago, thespaceinvader said:

R7 Astromech is probably a better choice for Tarn though.

I think R7 is only a better choice if you are primarily concerned about keeping Tarn alive. Until Tarn becomes the target his ability and R7 do nothing for your squad. I've got the same sort of problem with Tarn+R7 that I do with Dark Curse. They can be annoying to remove from the board but your opponent doesn't really have any reason to prioritize them over your more valuable ships.

M9-G8 turns Tarn into a support piece if he is ignored. He's able to give a squad-mate an offensive boost or to make it harder for an enemy to push damage through. If your enemy does decide to attack Tarn, his ability moves the Target Lock back to him and M9-G8 can help against each attack made against Tarn in a round. It then leaves Tarn (who is likely to be lower PS than much of what he faces) with a Target Lock to spend on offense. R7 has a larger defensive benefit when a single attack is being made against Tarn in a round but since it requires that the target lock be spent, it doesn't help to boost Tarn's offense.