Cheapest priced copy (Onslaught): $0.35 at Card Kingdom, near mint, their price list as of .
Ghosthelm Courier 
Creature — Human Wizard · 2/1 · Uncommon · Onslaught · #85
You may choose not to untap this creature during your untap step.
{2}{U}, {T}: Target Wizard creature gets +2/+2 and has shroud for as long as this creature remains tapped. (It can't be the target of spells or abilities.)
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
1 printing · $0.35 to $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Onslaught | 85 | Uncommon | $0.35 | $0.79 |
One ruling from Wizards of the Coast
- 4 October 2004It checks the creature type when the ability is announced and resolved, but once the effect is placed on the creature, if its creature type changes the effect still continues.