A Tyranitar that’s Metal and Fire instead of Dark and Fighting. A Mewtwo that isn’t Psychic. For one stretch of the Pokemon TCG’s history, the type printed in a card’s top corner didn’t have to match the Pokemon at all — and the small δ symbol next to the name was the only warning you got.
That mechanic is Delta Species, and it ran for six English-language sets between late 2005 and early 2007, built around a fictional research region called Holon. It’s also the source of a card we carry that gets mislabeled constantly: a PSA 10 “Gardevoir ex Delta Species” that most listings treat as an EX-era original but is actually a 2021 promo reprint of a slightly later card. This guide covers what the δ mechanic actually is, where it came from, and sorts out exactly what our in-stock copy is — and isn’t.
Delta Species (δ) reprinted Pokemon with off-type stats and typing, starting with EX Delta Species in October 2005 (Japanese: “Holon Kenkyuutou,” the Holon Research Tower expansion) and running through six sets into 2007. Our in-stock PSA10 Gardevoir ex Delta Species P 015/025 is currently listed at ¥10,749 (~$66) (update: currently sold out — restock requests via Quick Order) — it’s a 2021 25th Anniversary promo reprint, not an EX Delta Species-era pull, and this guide explains why that distinction matters.
Prices reflect our own catalog as of August 2026, in Japanese yen with USD shown at ¥163/USD for reference.
What Is Delta Species (δ)? The Mechanic Explained
Delta Species is a Pokemon TCG mechanic where a Pokemon is printed with a type it doesn’t normally have — the card looks like the Pokemon you know, but the type box and attack costs run on a different element entirely. The clearest documented example: Tyranitar, normally Dark/Fighting, was printed as Metal/Fire under the δ treatment. A small δ symbol next to the Pokemon’s name is the marker that tells you the card is a Delta Species print rather than a standard one.
The mechanic wasn’t introduced in isolation. It launched alongside a matching set of support cards built around a fictional research region called Holon — including “Holon’s Pokemon,” cards that could be played either as a Pokemon or as an Energy card, plus dedicated Holon staff Trainer cards and Holon-branded Energy. The whole package — off-type Pokemon, dual-purpose Holon cards, and Holon Trainers — is what collectors mean when they talk about the “Delta Species era.”
For anyone sorting a binder today, the practical upshot is simple: don’t assume a card’s type from the Pokemon alone. A δ Mewtwo isn’t guaranteed to be Psychic, and a δ Rayquaza isn’t guaranteed to be Dragon. Checking the printed type in the top-right corner — and looking for the δ symbol next to the name — is the only reliable way to identify one of these prints at a glance.
Where It Started: EX Delta Species and the Holon Storyline
The mechanic debuted in the English-language set EX Delta Species, released in October 2005. The set’s fiction is set in Holon, a research region introduced specifically to justify why so many Pokemon were suddenly showing up with the wrong typing — the Holon research staff and their equipment are the in-universe explanation.
Delta Species didn’t stop after one set. The storyline and mechanic continued into EX Holon Phantoms (English, May 2006), which shifted the setting to Holon’s “undeveloped region” and brought δ cards back for a second wave. Between those two sets, several more EX-era releases kept the mechanic running — the full lineup is in the timeline below.
For readers building out a wider EX-era or vintage Japanese collection, our Japanese old-back Pokemon cards guide covers the earlier era that predates Delta Species, and our Japanese Pokemon card rarities guide is useful background if you’re new to how Japanese-market TCG releases are structured generally.
Every Delta Species Set, 2005–2007
Delta Species ran across six consecutive English-language EX sets before the mechanic wound down:
| Set (English) | Release | Notes |
|---|---|---|
| EX Delta Species | Oct 2005 | Mechanic debut. Japanese counterpart: Holon Kenkyuutou |
| EX Legend Maker | Feb 2006 | Japanese: “Eidolon Forest” |
| EX Holon Phantoms | May 2006 | Second Holon storyline wave |
| EX Crystal Guardians | Jul 2006 | δ cards continue |
| EX Dragon Frontiers | Nov 2006 | “Delta Star” — shiny-style δ cards. Original home of Gardevoir ex δ |
| EX Power Keepers | Feb 2007 | Final set of the δ run |
The mechanic effectively closed out with Power Keepers in early 2007, after which the TCG moved on to new set mechanics without carrying Delta Species forward. The “Delta Star” cards in EX Dragon Frontiers are worth flagging specifically — they’re δ Pokemon printed with an alternate, shiny-style color treatment on top of the off-type mechanic, effectively stacking two rarity concepts into one card. That’s the same set that originally introduced the fire-type Gardevoir ex δ covered in the next section.
Our In-Stock Card: PSA10 Gardevoir ex Delta Species — a Naming Correction
Our PSA10 Gardevoir ex Delta Species P 015/025 (update: currently sold out — restock requests via Quick Order) is a card from the 2021 25th Anniversary promo card pack (Limitless set code s8a-P), not a card pulled from any 2005–2007 EX-era booster. The card it reprints, Gardevoir ex δ, originally debuted years after EX Delta Species itself.
Here’s the mix-up worth untangling. EX Delta Species does contain a Gardevoir at card number 93 — but that’s Holon Mentor (93/113), a Trainer card, not a Gardevoir Pokemon card at all. The set’s actual Gardevoir δ is a non-ex, Psychic/Metal-type card at 6/113. The ex-rare, fire-type Gardevoir ex δ that collectors usually mean when they say “Gardevoir ex Delta Species” first appeared in English in a later set: EX Dragon Frontiers, card 93/101 (November 2006).
If a listing says “Gardevoir ex Delta Species 93/113,” that number belongs to Holon Mentor, a Trainer card, in the actual EX Delta Species set. The fire-type Gardevoir ex δ card is numbered 93/101 and comes from EX Dragon Frontiers instead.
On the Japanese side, the original Gardevoir ex δ is understood to have been distributed through a 2006 constructed deck — commercial listings reference a deck named “Fuuin! Gardevoir ex” as its source, though we haven’t independently confirmed that deck name against a primary Pokemon source, so treat it as reported rather than fully verified.
What we actually stock is the 2021 reprint: promo card 015/025 from the 25th Anniversary promo card pack (s8a-P), officially listed under that number as “Gardevoir ex (δ species).” The s8a-P pack itself was distributed starting October 2021, was never sold on its own, and was obtained either by purchasing four packs of the 25th Anniversary Collection expansion (S8a) or through the 25th Golden Box bundle. It carries no regulation mark, which means it isn’t legal for official tournament play — a collector’s piece rather than a playable one.
The s8a-P pack runs 25 cards in total, numbered 001/025 through 025/025 on the official checklist, spanning reprints from multiple past eras. Two other cards we track come from the same pack: a reprinted Shining Magikarp at 010/025 and a reprinted Claydol at 016/025, both reprints of much older cards in their own right — a 2000 Neo-era original and a 2007-era original respectively — distributed the same way our Gardevoir ex δ copy was. If you’re tracking that specific promo pack as a set, our 25th Anniversary promo pack guide covers the full pack, and our Gardevoir cards guide covers Gardevoir prints outside the Delta Species mechanic as well.
Where to Buy Delta Species and 25th Anniversary Cards
We ship Japanese sealed product and graded singles worldwide from Tokyo with tracked delivery. Our PSA10 Gardevoir ex Delta Species P 015/025 is a graded single — one copy, and when it sells, it’s gone.
If you want to try pulling other cards from the same 25th Anniversary lineage — the expansion whose 4-pack purchase campaign is one of the two documented routes to the s8a-P promo pack — our S8A 25th Anniversary Collection Booster Box is currently listed at ¥79,800 (~$490). For other EX-era, Delta Species, or 25th Anniversary singles beyond what’s listed here, our Quick Order page is the fastest way to check current stock and build a mixed order.
Frequently Asked Questions
What is Delta Species (δ) in the Pokemon TCG?
Delta Species is a mechanic where Pokemon are printed with a type they don’t normally have — for example, Tyranitar printed as Metal/Fire instead of its usual Dark/Fighting. A δ symbol next to the Pokemon’s name marks these cards, which were tied to a fictional Holon storyline and matching support cards.
When did Delta Species cards first come out?
The mechanic debuted in EX Delta Species, released in English in October 2005. The Japanese-language counterpart, Holon Kenkyuutou (Holon Research Tower), released October 28, 2005. The mechanic continued through five more EX-era sets into early 2007.
Is your PSA10 Gardevoir ex Delta Species card from the original EX Delta Species set?
No. Our copy is card 015/025 from the 2021 25th Anniversary promo card pack (s8a-P), a reprint. The card it reprints, the fire-type Gardevoir ex δ, originally debuted in EX Dragon Frontiers (93/101) in November 2006, not in EX Delta Species itself.
What is card 93/113 in EX Delta Species, then?
That number belongs to Holon Mentor, a Trainer card, not a Gardevoir. EX Delta Species does include a non-ex Gardevoir δ card, but it’s numbered 6/113 and printed as a Psychic/Metal type rather than fire.
Where can I buy Delta Species and 25th Anniversary Pokemon cards from Japan?
We ship Japanese sealed product and graded singles worldwide from Tokyo. Our PSA10 Gardevoir ex Delta Species P 015/025 is currently listed at ¥10,749, and the S8A 25th Anniversary Collection Booster Box is currently listed at ¥79,800. Use our Quick Order page to check current stock on other Delta Species-era or 25th Anniversary pieces.
Picked for this article
📩 Get member-only sale alerts & coupons
Sale alerts, coupons and restock notices by email — straight from Tokyo.
