Here's my attempt at a fun 30 card speed mutation deck for pvp/top50. I'm still experimenting with it, but it does have a pretty good win rate so far and not that many weaknesses that I'm aware of.
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6ts 6ts 6ts 6ts 6ts 6ts 6u1 6u1 6u3 6u3 6u3 6u3 6u3 6u3 6u4 6u4 6u4 6u6 6u6 6u6 74a 74a 7dm 7q1 7q1 7q1 7q1 7q1 7q1 7t9 8pj
In the first version of this build I used blessings, chaos powers, etc. to try and capitalize off the deja vu ability. Unfortunately, it didn't work out that well. For one thing, it uses up too many useful card slots in the deck. And second, the pumped up deja vu's would usually pale in comparison to an improved mutant. Though I still think the deja vu has a lot of potential for this kind of deck - fast, cheap, mutation fodder - so I retained all 6 of them.
In the new build, the supernova's provide just enough time quanta to fuel the deja vu's + all the potential mutation abilities. I don't use quantum pillars. I've found the right amount of amethyst pillars to be about 6 provided you take mark of chaos. It might also work with mark of time, but with an additional pillar.
The deck handles shields using 1 steal and 1 explosion + 2 momentum's. This tends to work out nicely. As for creature control, it can be a bit unpredictable, but mutating the opponent's units does provide some protection. I also found the ideal number of druids and improved mutations to be 3 of each. If the opponent dispatches the druids you can still get a strong mutant through with the improved mutation. While if you have too many druids you'll end up draining your life and entropy quanta. Last point, in terms of creature balance, 6 deja vu's + 2 werewolves guarantee's a creature in the first hand + it doesn't rely completely on the supernova for early mutations. Those are my thoughts. Let me know what you think.