In this case, I can
totally see calling
XY: Phantom Forces the
worst of the XY-series,
but you leave out the reason that is hard to argue:
Lysandre's Trump Card was released in
XY: Phantom Forces.
When the-powers-that-be release the first card to be banned in Modified (Standard) play in about 15 years, and only the third such card in the history of the game, that is a
very bad thing. Not only because the unbalancing effect it had upon the game while present, but the
continuing imbalance caused by it being gone. You brought up Night March... what do you think
Lysandre's Trump Card helped to counter? Unlike with
Karen,
Lysandre's Trump Card allowed a Night March player to try and set up over and over again, but Night March decks have a lot of "moving pieces": cards that need to be played with at least some degree of skill or else the whole thing breaks down. That breakdown can take many forms; usually whiffing on a badly needed OHKO or accidentally tossing something you shouldn't. Even when Night March got all its goodies from the discard pile back, having to do it all over again gave the deck fits. If you look, other cards were probably designed with the assumption
Lysandre's Trump Card would be a factor of competitive play and became more potent for its absence.
You listed a few cards you thought of as reasons for
XY: Phantom Forces not to be the worst set... but it mostly just exposes your own bias.
Battle Compressor,
VS Seeker, etc. all enabled some potent strategies... and ruined some as well. That is how it works in a TCG that isn't well balanced. Pokémon is far from the worst, for all I know it could be the best, but that is mostly because customers don't demand better, so we get 100 card expansions where 50 cards are hopeless, 25 have a slight chance, 15 are good, and 10 you
have to have, either because they are vital to one of the major archetypes, or to
all decks from that point on. @
[email protected] Night March got a lot of grief because it was
popular. Never mind that it was a great example of diversity and (for the Pokémon TCG) innovation. The normally filler Evolving Basics and Stage 1 forms of some other cards got a useful attack, and with a lot of skill in deck build and play, it became very competitive. At a time when too many were mad that you needed really rare cards (often Pokémon-EX) to have a competitive deck, we got Night march; the focus ended up on Commons and Uncommons, maybe with a
Mew-EX (an inexpensive Pokémon-EX due to its availability).
Night March never won the World Championships. It was only seen as the top deck for three to six months of its time in Standard. I ran it and I certainly wasn't going undefeated. There are a few decks that really were hurt by its existence, but most that were
also struggled against the rest of the competitive metagame. For that matter, look at what Night March used (and basically needed); because of modern
Vespiquen decks, I assume
Battle Compressor merely helped, but take away the overpowered stuff that shaped most of the metagame like
Battle Compressor,
Double Colorless Energy,
Professor Juniper/
Professor Sycamore, and
Shaymin-EX (
XY: Roaring Skies 77/108, 106/108) and Night March would never have been.
Double Colorless Energy, in particular, is essential to it.