Straight to the point, Grievous is alright. The problem is that the rest of his team is not. Currently, GG is the only one on a separatist team to do decent damage, so any team with a thrawn will wreck him by fracturing him, taking out the only damage output on a Sep team unless a geared up droideka can do something. And GG’s unique cripples his team. It actually will strip stacks of droid battalion from B1 faster than he can replenish them, without even taking the enemy attacking B1 into account. Magnaguard is very underwhelming. I have seen him take a grand total of 1 bonus turn in the 6 arena matches I have played with him, as he keeps dying before his turn. This is because if magna is stunned, he skips his bonus turn and then dies. If someone else has 100% TM, they can kill magna before his bonus turn starts. If magna has any damaging debuffs like burning or a DOT, he starts his turn and immediately dies. Even if all of this gets fixed, they can maybe win on offense against NS and Revan teams. They will still lose to Traya and CLS teams on offense, and lose to everyone on defense because of their lack of a pretaunt or anything to stop them from focusing down the frail B1. Unless droideka turns out to be an absolute god, which he did not appear to be in his marquee, the Seperatists will be unable to challenge the meta in any way.