General Rules and Eratta

    In addition to culling a large portion of cards available (though there's still a sea of cards to choose from), I felt like some balancing and errata would make for more interesting games.

• Firstly: All Pokémon printed before Diamond and Pearl have the following weakness modifier: Basic Pokémon: +10, Stage 1: +20, Stage 2: +30, Pokémon EX: x2

    Diamond and Pearl introduced maybe the greatest feature in all PTCG-dom. It wasn't Lv.Xs, it wasn't separating Trainers, Stadiums, and Supporters, and it sure as hell wasn't Pokémon SP (yeah that was Platinum, whatever). It was changing weakness multipliers to additive damage. Unfortunately, all the older cards were at an immediate disadvantage because mid power damage would score KOs that Diamond and Pearl cards could avoid. By making this change, it's now way easier to build decks around older attackers without being afraid of them getting dunked on immediately. 

• Secondly the Lv.X Rule: All cards that apply to in play Pokémon ex also apply to Pokémon Lv.X (e.g. Silver Bangle causes attacks to do 30 more damage to Pokémon Lv.X). (This effect does not go both ways, so a card that affects or is affected by in play Pokémon Lv.X does not apply to Pokémon ex.)

Boy, that is an Extreme Attack

    This one basically just makes older cards from the EX series more viable in stopping Lv.X decks. In addition to this, the fact that it's "one way" means that cards like Flygon Lv.X aren't sniping ex Pokémon for easy 2 prize turns. 

• Retro-Mode cards: Any card that applies to Pokémon-EX, Pokémon-GX, Pokémon V, or Pokémon VMax now instead applies to Pokémon ex and Pokémon Lv. X

    Kind of a no-brainer. Effectively just groups all of these cards into the newly coined "Rule Box" group. Which they don't seem to be doing anything else with officially outside of a handful of cards. Techs like Phoebe now have even more use than they do in their proper formats.

• Type Rollback: Any instances of [N] (Dragon) or [Y] (Fairy) are now read as [C] (Colorless)

Why use dragons when you
can use Wigglytuff ex?

    Those types didn't exist back in the day, so now they refer to the types that their majorities used to belong to.

    There are a few more changes and specific errata that will be elaborated on next.