Cheapest priced copy (Final Fantasy Commander): $1.99 at Card Kingdom, near mint, their price list as of .
Champion's Helm 
Artifact — Equipment · Rare · Secret Lair Countdown · #64
Equipped creature gets +2/+2.
As long as equipped creature is legendary, it has hexproof. (It can't be the target of spells or abilities your opponents control.)
Equip {1}
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
11 printings · $1.99 to $69.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2011 | 244 | Rare | $3.99 | — |
| Commander Masters | 375 | Rare | $2.79 | $4.99 |
| Commander Masters | 601 | Rare | — | — |
| Commander Masters | 654 | Rare | $5.99 | $8.99 |
| Final Fantasy Commander | 337 | Rare | $1.99 | $4.49 |
| Kaladesh Inventions | 7 | Special | — | $69.99 |
| Fallout | 228 | Rare | $2.29 | $2.99 |
| Fallout | 482 | Rare | $3.99 | $2.99 |
| Fallout | 756 | Rare | — | $3.49 |
| Fallout | 1010 | Rare | — | $2.99 |
| Secret Lair Countdown | 64 | Rare | — | — |
One ruling from Wizards of the Coast
- 22 September 2011It's possible for a Champion's Helm you control to be attached to a creature an opponent controls (if an opponent gains control of your equipped creature, for example). In this case, the creature couldn't be the target of spells or abilities you control, as you are an opponent of the controller of the creature with hexproof.