So. So far we have Wildewood, Aquachemantics and Aerochemantics. We can probably expect Geochemantics and Pyrochemantics later, along with Wyrdwood.
These new skills and roleplay devices are still new and malleable, especially the ones which don't exist yet. My idea is for Earth to get a train.
Celest gets a ship on Water, Hallifax gets a zeppelin on Air, Magnagora should get a train. Easily place trcks all over the Mountains, or catacombs, and have it move about like that. Trains, especially steam locomotives, are inherently Magnagoran (Hallifax would come up with something like the bullet trains: runs on electricity and magnets), not the least because Magnagora is steampunk incarnate. It wouldn't be hard to make a train 'tainted' or 'Magnagoran'. Just put a few spikes on it, some carvings of the Demon Lords/Earth Lords and whatnot.
Trains are awesome.
I don't know what could appear on Fire. Maybe some sort of lava/fire submarine?
A masked taurian exclaims, "Sugoi! Gorlois-kun is kawaii, uguu~!"