Neutron shark is one of my favourites in my best deck. The ability to destroy artefacts and/or priority targets depending on the situation at the cost of one of your own creatures (often the shark itself) is great for a discard. It helps me thin out the deck, destroy artefacts that could be hard to deal with and is a play/reap/fight card and is fairly versatile. And you can end the effect by killing the shark itself.

I don't know if these are actually under-rated, but I tend to surprise opponents because of the uncommon effects.

Guilty Hearts : because capturing my hard-earned Aember is really annoying

Mindwarper or Hypnotic Command : there is something very pleasing to have an enemy creature capturing from its own side

Selwyn the Fence : stealing the Aember you've captured from your opponent is just as pleasing

Dysania : for that opponent archiving for Epic Quest or Library Access play

Skippy Timehog : just to screw with the opponent who has set up that overwhelming board

6 hours ago, MediatorJ said:

I don't know if these are actually under-rated, but I tend to surprise opponents because of the uncommon effects.

Guilty Hearts : because capturing my hard-earned Aember is really annoying

Mindwarper or Hypnotic Command : there is something very pleasing to have an enemy creature capturing from its own side

Selwyn the Fence : stealing the Aember you've captured from your opponent is just as pleasing

Dysania : for that opponent archiving for Epic Quest or Library Access play

Skippy Timehog : just to screw with the opponent who has set up that overwhelming board

Skippy Timehog can be incredible if timed well. Can keep an opponent from coming back in some cases, when you've already got the lead.