Thats two Mana and a discarded card, a very economical price, for +6/+0 to your Shivan Dragon or +5/+0 to your Serra Angel
That honor instead went to the Rare Holo Entei cardlikely building on the hype from the then recently-released Pokmon 3: The Movie, which heavily featured the Fire-type Legendary
The archetype is primarily focused on Fusion Summoning, with powerful "El Shaddoll" boss monsters that punish Special Summoning, versatile Spells and Traps for Fusion Summoning, and Main Deck monsters that can provide advantage when sent to the GY as Fusion Materials
The design team simply hasnt made it a priority
This Rank 4 monster requires 3 Spellcaster monsters for its Xyz Materials, and it gains 200 ATK for each Spell Card in your GY
3 Talrand, Sky Summoner Overwhelms the Board With Drakes 4,698 Decks on EDHrec.com Talrand, Sky Summoner often appears in other blue Commander decks to provide a payoff for so many spells being cast, but Talrand shines most of all as a proper commander