Cheapest priced copy (Innistrad Remastered): $0.99 at Card Kingdom, near mint, their price list as of .
Somberwald Sage 
Creature — Human Druid · 0/1 · Rare · Avacyn Restored · #194
{T}: Add three mana of any one color. Spend this mana only to cast creature spells.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
4 printings · $0.99 to $5.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Avacyn Restored | 194 | Rare | $1.29 | $3.99 |
| Innistrad Remastered | 215 | Uncommon | $1.29 | $1.99 |
| Innistrad Remastered | 418 | Uncommon | $0.99 | $5.99 |
| Midnight Hunt Commander | 144 | Rare | $0.99 | — |
3 rulings from Wizards of the Coast
- 1 May 2012Mana produced by Somberwald Sage can't be spent on noncreature spells that would put creature tokens onto the battlefield.
- 1 May 2012Mana produced by Somberwald Sage can be spent on any part of a creature spell's total cost. This includes additional costs (such as kicker) and alternative costs (such as evoke costs).
- 1 May 2012Mana produced by Somberwald Sage can't be spent on activated abilities, even ones that put a creature card directly onto the battlefield, such as unearth or ninjutsu.