Cheapest priced copy (Commander Masters): $0.35 at Card Kingdom, near mint, their price list as of .
Renowned Weaponsmith 
Creature — Human Artificer · 1/3 · Uncommon · Core Set 2020 · #72
{T}: Add {C}{C}. Spend this mana only to cast artifact spells or activate abilities of artifacts.
{U}, {T}: Search your library for a card named Heart-Piercer Bow or Vial of Dragonfire, reveal it, put it into your hand, then shuffle.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
4 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Masters | 114 | Common | $0.35 | $0.49 |
| Fate Reforged | 48 | Uncommon | $0.35 | $0.49 |
| Jumpstart 2022 | 338 | Uncommon | $0.35 | — |
| Core Set 2020 | 72 | Uncommon | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 12 July 2019The mana generated by Renowned Weaponsmith’s first ability can’t be spent to activate abilities of artifact sources that aren’t on the battlefield.
- 12 July 2019Activated abilities contain a colon. They’re generally written “[Cost]: [Effect].” Some keyword abilities, such as equip, are activated abilities and will have colons in their reminder text. You can’t spend mana added by this ability to pay costs of triggered abilities of artifacts such as the first ability of Chandra’s Regulator.