Caring about the mana value of spells is a theme that runs in opposition to traditional Spellslinger strategies that want to chain together cheap, low-cost, and efficient instant and sorcery spells, and consistent token generation gives the deck a more impactful board presence to fend off attacks
Theyve been around since Llanowar Elves all the way back in Alpha , the very first Magic set, and have appeared all over the multiverse across over 600 creature cards
Enchanted cards sit at the top
1 Vivid Meadow
While there are other weird things you can do with activated abilities on creatures, the bread and butter of the deck will be cards like Will, Scion of Peace for cost reduction, Beacon of Immortality for big mills, and Sphinx of the Revelation to draw a lot of cards
Hence the reason why hes Iron Goblin just like Bosh was Iron Golem, and why he sacrifices artifacts to an ability where casting cost matters