Ive got a list of things that I think will help you build the deck, and which have a very good chance of inclusion
Instead, you can fully recreate Fang and Vanille's transformation thanks to one of my favorite Magic mechanics, Meld
The first counter allows Urzas Saga to tap for colourless mana, the second adds an ability you can pay two for to put a 0/0 Construct into play that gets +1/+1 for each artifact you control, and the final ability lets you search your library for an artifact with a mana cost of 0 or 1 and then put it straight into play
For Rowan, a Rakdos deck where you pay life for an effect can get that payoff easily
Vivi Ornitier, one of the most hyped cards from the set, made the cut in one list working as a scaling creature that can deal damage without entering combat while also making mana each turn
legal targets are a creature, a player, a Battle or a planeswalker