Cheapest priced copy (March of the Machine Commander): $4.99 at Card Kingdom, near mint, their price list as of .
Conjurer's Mantle 
Artifact — Equipment · Rare · March of the Machine Commander · #12
Equipped creature gets +1/+1 and has vigilance.
Whenever equipped creature attacks, look at the top six cards of your library. You may reveal a card that shares a creature type with that creature from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Equip {1}
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $4.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| March of the Machine Commander | 12 | Rare | $4.99 | — |
| March of the Machine Commander | 99 | Rare | $4.99 | — |
2 rulings from Wizards of the Coast
- 14 April 2023If the equipped creature is no longer on the battlefield as the triggered ability resolves, use its creature types from when it was last on the battlefield.
- 14 April 2023A creature "shares a creature type" with the equipped creature if they have at least one creature type in common.