New mutations for Patch 4.10.0:

Enhanced Defenses

Barrier - Enemy units gain a temporary shield upon the first time they take damage.

Going Nuclear - Nukes are launched at random throughout the map.

Photon Overload - All enemy structures attack nearby hostile units.

Maintaining an army will be hectic this mutation as Cradle of Death has lots of tight spaces and could make keeping both your truck and your army alive. Commanders with free units, and Artanis, will be a popular choice for players, though Abathur, Dehaka, and Kerrigan should have not much trouble here.

Double Trouble

Kill Bots - Invincible Kill Bots attack your forces until they hit their predetermined kill limit and shut down.

Propagators - Reality warping sludges are crawling towards you. Anything they touch is turned into a copy of the sludge.

Even if you clear out the whole map, the bots and poops will still spawn from the shuttle bays. Players will have to stand units still for the kill bots while at the same time killing the poops. Raynor, Stetmann, and Zagara could be good here.

And Drops And Rifts

Aggressive Deployment - Additional enemy units are periodically deployed onto the battlefield.

Void Rifts - Void Rifts periodically appear in random locations and spawn enemy units until destroyed.

Early game armies are key here. Snipe Void Rifts ASAP while keeping your army on the map to intercept drops. Lots of commanders can be good here. It just gets really hectic.

Catch the Train

Afraid of the Dark - Vision provided by all sources is extremely limited except when in view of your camera.

Short-sighted - Player units and structures have reduced vision range.

Speed Freaks - Enemy units have double their normal movement speed.

Not expecting much trouble on this mutation. Vision will be rather irritating, and the attack waves hit faster, but this for the most part is plain Oblivion Express.