I can see this being run in some rogue deck 4-4, and then some attacker. Think about it. You can Mentor for three Slowpoke early, and you only need 1 Slowking out of 4 in the deck in play by the time your opponent KO's one of your pokemon. Then the one Slowking searches for a second Slowking. Then you evolve with that and use it to search for the third Slowking, which does it again. Ideally it gets you all of the Slowkings out at once. The last one could search for a Warp Point or something if a Slowking ended up being active. After that, if your opponent isn't using Psychic Lock, every time they knock something out, you can literally send up a random basic and search for every single card it would need to be an attacker. I like the idea of Magmortar, Scramble Energy, Magmortar Lv.X, and what ever else your heart desires. If you use a Stage 2, this would probably be the Rare Candy. You can use any attacker you want to go with it and abuse Scramble. Whenever that gets knocked out, just send up whatever basic and use four Trump Card powers to transform it into an instant attacker. I'd even think you can even use multiples of different attackers in such a deck to counter whatever deck you're playing against.
I think it is possible. Perhaps Sableye CG to try to get around Psychic Lock?
Anyway, my rating varies heavily depending on how you use it, but I'll slap a 7.5 out of 10 on it, but it has deadly potential; a possible danger in the future.
