I wouldn't call it elegant, more referential as any other part of GO I guess.
Waver alludes to how when you beat the Septum stage.
https://www.youtube.com/watch?v=bOgK...qFf8oK&index=5
1:00
Pretty much exactly the same as how Shirou summoned Saber.
Iri put a Einzbern territory establishing magic circle in Shirou's basement. Shirou gets attacked by Lancer, goes into basement to find a better weapon. "Bonds of Fate" from Avalon as a catalyst. Grail summons Saber through a magic circle not made for summoning.
FGO-kun steps into giant summoning circle made to re-summon Demon Pillars endlessly after they die. "Bonds of Fate" from adventure as catalyst. Summons the Servants.
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