Pokemon TCG has a few options for different types of Energy, and drawing inspiration from those would make sense for Pokemon TCG Pocket
Then, once its out, each time its user casts a spell, they can bounce back either a spell on the stack or a nonland permanent on the field back to its owners hand, turning every spell they have into a counterspell and allowing them to clear the field for a game-winning all-out attack, or even removing curses and other effects from their own permanents
Invasion of FioraInvasion of Fiora Conspiracy 1 & 2 were among my favorite sets in the past 10 years
None of these combo pieces are hindered by Zirdas Companion restriction, and you have ample access to tutors, drawpower, and recursion between red and white
However if you're like me and catching em all really isnt your thing (and with 719 to get, who could blame you?), then there are still plenty of other distractions on offer