PSA 10 rates 25-35% on modern card stock
Remember that this applies to attacks done by the opponents Pokmon, and not chip damage from Darkrai EX or Water Shuriken Greninja
However, Mewtwo is a very popular Pokemon, so this card might hold its value better than Marnie's Grimmsnarl, for example, but don't expect it to soar with the English version setting its ceiling
Well, it will feel that way
For the sake of simplicity, lets call all of these cards "cyclers" (that all can be cycled), and my selections meet the criteria of either a) costing a single mana to discard, b) providing additional value when cycled, or c) ideally both: Greater TanukiGreater Tanuki, Altanak, the Thrice-CalledAltanak, the Thrice-Called, and Shefet MonitorShefet Monitor serve as ramp sources, while Generous EntGenerous Ent, Eagles of the NorthEagles of the North, and Spinewoods ArmadilloSpinewoods Armadillo can help with hitting land drops