Konami’s Yugioh-card website has a news article up that confirms the name “Ritual Beast Ulti-Apelio” for the Secret Forces Booster set.

For those who haven’t been following the Ritual Beasts, their Japanese names creates a complex naming structure, where the ritual beast theme is technically comprised of several sub-themes. To summarize:

Ritual Beast -> the shared name of an Ainu-themed “Contact Fusion” archtype.
Ritual Beast Tamer -> The Psychics who commune with nature and command the ->
Spiritual Beasts -> The Main-deck creatures of various types. They combine together to form
Ritual Beast Ulti-[Apelio etc] -> “ultimate” forms of the Spiritual Beasts.

Due to this naming scheme you are not allowed to use “Ritual Beast Ulti-” monsters [the Fusion bosses] as fusion material for other “Ritual Beast Ulti-” monsters (Except with the tentatively named “Bond with the Ritual Beast” Spell Card).

This doesn’t change how they’ve been used up to this point in online simulators. We just finally have an English name to call the fusion monsters.

They be Rituals.

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