Honestly, if the Lostgar player was smart, he would Lost Zone the Regice instead of the Magikarps. Then, unless the Gyarados player would be playing another Regice (which I have never seen), the Gyarados player would be stuck with 2 Magikarps in his hand. Unless the Gyarados player drew into a Volkner's Philosophy, he would either play the Magikarps down and be stuck with 2 Bench Sitters, or have 1 Magikarp in the Lost Zone that turn and another in the Lost Zone another the next turn. And Lostgar could tech in Honchkrow SV, and then bring Magikarps back on bench, and it would be possible either way because Lostgar runs Seeker, which automatically frees a bench space. And it would be bad for a Lostgar player to kill the Magikarps because in helps the Gyarados player, because you draw a prize (Lostgar doesn't win by prizes), and they get a Magikarp in the discard pile. The only way for the Magikarp to get back in the discard would be to hit a heads on a SSU and put back in their hand to be discarded by a Volkners, Regice, or Junk Arm (but Regice should be in the Lost Zone, so only Volkners or Junk Arm). And I have found out that a Mesprit drop and a Judge absolutly skrews over Gyarados, because it kills their recovery and they can't use an Uxie drop because of Psychic Bind. In the end I would say maybe 20-80 in favor of Lostgar.