I can see Regigigas and Groudon being used in The Truth. Regigigas, not as much, because of the high energy costs, which requires a while to setup, and good number of DCE's, unless you want to try shoving basics onto it for 3-4 turns. Also, a Terrakion revenge kill will completely destroy it. I see Groudon doing better, though. The only thing that can really OHKO it is a Kyurem with 70 damage on it, or 90 if it has Eviolite on it. Also, just to point it out, a Magnezone will need 5 ENERGY to take out a Groudon-EX with Eviolite. Groudon can be powered up with the Fighting energy which could be in the deck if you're starting/stalling with Donphan. Also, in games when you can set up relatively early, Groudon can probably use Stamp twice, just so that Giant Claw will do 120 damage later on.