Its much more fragile once it's in play, but at least a 3/4 creature for 4 mana isnt too bad
Many of the myr have tap-to-activate activated abilities, meaning you can tap them as mana abilities or other utility effects before combat and only risk something safe like a Darksteel Myr
So, building around TAUC mechanics like convoke and station is a way to access game-breaking tempo plays essentially for free, as a reward for doing something which is already valuable on its own at all points of the game
Related As far as other promotional Lorcana cards go, according to TCGPlayer, the Elsa Snow Queen D23 promo card can fetch a hefty $5000
Cards that Both Create and Use Blood Tokens Anje, Maid of Dishonor is one of the best creatures in the set when it comes to both creating and using Blood Tokens
Mole Man, Moloid Master Mole Man, Moloid Master is a fresh spin on Crucible of Worlds that comes with a landfall ability to reward using it and self-mill to fuel it