GAS

General Strategy: With comparable gear/relics this should be an easy win on offense – however you will struggle against all R7 squads if your toons aren’t at least R5  R7 GAS at least is a must for most arena shards.  Most people prefer to mod GAS for defense/protection because it makes the mirror matchup easier, whereas others prefer a more offensive CC/CD/offense build which fares better against most other squads – the matchup is easily winnable on offense with either mod setup.  The GAS mirror is very forgiving in terms of RNG since the AI almost never targets 5s first.  The turn order can be unpredictable due to Rex’s Form Up ability which grants TM to your entire team but this rarely matters in the long run.  If your Rex is faster us his Form up ability and then whittle down the enemy GAS protection while making sure to daze and increase the cooldowns of the enemy team with your GAS.  Most people prefer to give ARC’s turret to whoever has more TM between Echo and Rex.  If your Rex is slower, your GAS will slowly counter away at the enemy GAS until your team can go.  Once the enemy GAS is in cover, immediately target the enemy 5’s, whereas the enemy team will usually target your weakest toon (usually Rex).  GAS will likely Advance before 5’s can be killed, so if yours gets up first then kill 5’s.   The fight can get unpredictable after this, but the general idea is to keep the enemy GAS in cover and then kill Rex first, then either Arc or Echo (order doesn’t seem to matter much here).  Make sure you save Rex’s nuke for when GAS has high protection or when all the other clones are killed.  Once all the other clones are killed you should be able to finish off GAS easily.