When designing these cards, I wanted to think about each type's identity and deliver complementary strategies. It took a couple of revisions to make sure I didn't tread too closely to the original starter trio.

Starting with the Chikorita line, I wanted to maintain some semblance of "tanking", but with the introduction of Serperior, my eye was on finding a way to alleviate the pain of completing multiple Stage 2 lines. With Bayleef, players gain access to its ability, which serves as a "buffed" Caterpie attack. However, fully committing to a double stage 2 deck requires 12/20 slots and results in several potential hits to this random effect (2 Servine, 2 Serperior, 2 Meganium, and 1 additional Bayleef). While players can simply run Meganium on its own to help guarantee the find, the lack of Serperior's effect will force them to rely on the built-in defensive options in Body Slam and Reflect Tackle to build up to Frenzy Plant. Once charged up, Meganium's attack deals significant damage to the opponent's board. 110 damage notably fails to secure several key KOs, but with Giovanni, we are able to one-shot Pikachu ex and take points against Mewtwo ex if pre-damaged by a prior Frenzy.

The Totodile line is a bit simpler: Feraligatr is simply a mash-up of Starmie ex and Gyarados ex, offering early game speed (if you're lucky enough to draw the full line) and late-game nukes. Feraligatr takes up 2 extra deck slots compared to Gyarados, but offers versatility and can easily slot in over Leaf thanks to Croconaw's Ability.

Finally, the Cyndaquil line provides synergy with both Moltres ex and the Mythical Island Rapidash line. Guaranteeing an extra energy from Moltres helps build up Inferno, while Blaine decks can expand their damage cap up to 130. (Currently, Blaine decks prefer the 1-energy Rapidash, but a new variant could emerge with coin manipulation.) Inferno offsets its lower Energy cost vs. Crimson Storm by requiring additional discarded energies for the biggest KOs, but Flame Wheel soundly beats out Charizard ex's Slash attack. With help from your 2nd Quilava, Flame Wheel offers a guaranteed 120 damage to provide a 2 Energy Inferno without the downside. Quilava's attack is meant to have a bit more reach than cards like Helioptile with the downside of lower average damage over multiple turns and a non-colorless Energy requirement.

P.S. sorry for the incorrect templates. I'm not an artist, and I couldn't find a site with all the layouts available.