Using the previous scenario, my character is Nightbird in alt mode. What is the timing there? Does the Decepticon Shockwave player take 1 damage each time an action hits the play area or after the Brainstorm resolves?
I.E. My Nightbird is at full HP (11) and his Shockwave is at 3. Who wins?

Here's what happens. Your opponent starts to play Brainstorm, this causes Nightbirds ability to trigger, but that effect doesnt resolve immediately. Continuing to resolve Brainstorm, your opponent then plays System Reboot. Another Nightbird trigger happens, which, again, doesnt resolve immediately. The System Reboot resolves, causing Shockwave to trigger four times. Continuing to resolve Brain Storm, your opponent then plays the second System Reboot. This causes another Nightbird trigger. The second System Reboot causes another four Shockwave triggers. Now that Brainstorm has resolved, we start resolving triggers, beginning with the ones that triggered most recently and working backwards. The four Shockwave triggers caused by the second System Reboot happen one at a time. Next, the Nightbird trigger caused by the second System Reboot happens. Next, the Shockwave triggers caused by the first System Reboot happens. Next, the Nightbird trigger caused by the first System Reboot happens. And finally, the Nightbird trigger caused by the Brain Storm happens. At any point, if resolving one of these triggers causes a player to KO their last character, that player loses the game. If Shockwave was at 3 and Nightbird was at 8 at the beginning of this sequence, Nightbird is going to lose.

Source: Wizards of the Coast (2019-11-22)    【Link to Ruling】

Tags: Nightbird, Enigmatic Agent, Decepticon Shockwave, Cybertron Commander, Brainstorm, Brainstorm