GAS event is broken

as for modding I'd suggest high h/p on magna and b2 with decent tenacity so they don't get dazed/stunned. If you have the zeta on droideka try to make him go just after echo (since his aoe dispels) and let him roll out so he can assist. B1 should be modded for offense+speed and focus on getting him to relic 4 at least since he assists a lot which helps with topple gas and killing clones. Only use b2 aoe if magna has taunt.

Hope this helps a bit