For Olivias activated ability Zirda, the Dawnwaker will prove to be an asset to make her ability cheaper
Most of these effects read: If you would draw a card, draw two instead. So thats our focus here, replace one draw with two (plus Eruth because it fits a similar niche)
One of the biggest downsides of playing a mutate deck is being weak to removal, but Cromat's protection helps to counteract that as it can regenerate itself to prevent it from being destroyed
Mime (#95), and Porygon (#103) - that have an "a" and "b" version
So, given all of that, you can expect the next update in late June or early July
There are a few other characters that have been released over the course of the game that let you ready Simba after youve triggered Simbas ability, so that Simba will not be vulnerable to challenges