Before last night I'd have said Bastion which I'm still a huge fan of. R4'd before I could even dupe him and now sig R200.
But I pulled Karolina yesterday and I don't know how to use her yet but I tested her out a bit and I truly like what she does.
Just listen to your gut and go for it. They are all amazing champions.
I got this exact nexus in the first round of compensation. I went with Karolina. No regrets, she is r3just hoping Kabam doesnt try anything with the rebalance