With synchro monsters, you have to perfectly balance the ratio of tuners and non-tuners in your main deck, and with fusion monsters you need to draw the exact fusion requirements, and somehow have Polymerization
(If a permanent with a stun counter would become untapped, remove one from it instead.) P/T Set Number 347 Language Italiano Legal Formats Alchemy, Brawl, Commander, Competitive Brawl, Historic, Legacy, Modern, Pioneer, Standard, Timeless, Vintage Rulings (6/6/2025) The value of X is calculated only once, as Omega's ability resolves.
In terms of Valkyrie targets though, few are as potent as World Legacys Mind Meld
[1] Common cards have relatively simple mechanics and abilities, since they serve as the basic building blocks for any Lorcana deck
In the case of the God card, it was summoned in 3 releases to ensure that it was not subject to these restrictions