Cheapest priced copy (Edge of Eternities): $0.35 at Card Kingdom, near mint, their price list as of .
Steelswarm Operator 
Artifact Creature — Robot Soldier · 1/1 · Uncommon · Edge of Eternities · #80
Flying
{T}: Add {U}. Spend this mana only to cast an artifact spell.
{T}: Add {U}{U}. Spend this mana only to activate abilities of artifact sources.
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Edge of Eternities | 80 | Uncommon | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 25 July 2025An “artifact source” is any object with the card type artifact. This means you could spend the mana from Steelswarm Operator’s last ability to activate an ability of an artifact you control or an artifact card in your hand or graveyard, for example.