Living metal is a static ability that causes the Vehicles to also be creatures as long as it's your turn
Red Red has access to a lot of damage-based removals, which is normally very good in 60-card constructed because Lightning Bolts and Shocks are very efficient
Like most monsters introduced in the movie unrelated to Dark Magician and Blue-Eyes White Dragon, Rare Metal Dragon has never received an alternate form, so it doesn't have related cards that look similar to Rhydon and Rhyperior in appearance
This is great due to the many options we have to find and discard energy, including EarthenVessel, Radiant Greninja, the brand new ACE SPEC Energy Search Pro, and the regular Energy Search
Transitioned over to an option on a planeswalker and the effective mana value clearly shoots up along with the increased relevance of the effects given what they are protecting as well as what they are not costing you in deck construction terms
Usually from shady sources that arent accountable and thrive on secrecy
