Cheapest priced copy (Eldritch Moon): $0.39 at Card Kingdom, near mint, their price list as of .
Curious Homunculus // Voracious Reader 
Creature — Homunculus // Creature — Eldrazi Homunculus · 1/1 · Uncommon · Eldritch Moon · #54
{T}: Add {C}. Spend this mana only to cast an instant or sorcery spell.
At the beginning of your upkeep, if there are three or more instant and/or sorcery cards in your graveyard, transform this creature.
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Instant and sorcery spells you cast cost {1} less to cast.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
1 printing · $0.39 to $3.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Eldritch Moon | 54 | Uncommon | $0.39 | $3.49 |
5 rulings from Wizards of the Coast
- 13 July 2016If you don't have enough instant and/or sorcery cards in your graveyard as your upkeep begins, Curious Homunculus's last ability doesn't trigger. If you don't have enough as the ability resolves, the ability has no effect.
- 13 July 2016If an instant or sorcery spell has {X} in its mana cost, choose the value for X first, and then reduce the cost by {1}. For example, Dark Salvation with X chosen as 2 costs {3}{B} to cast if you control Voracious Reader.
- 13 July 2016Mana from Curious Homunculus's first ability can be spent to cast a spell that has generic mana in its additional cost, such as Borrowed Malevolence with both modes chosen. It can't be spent to pay costs during a spell's resolution, such as the cost Convolute prompts a player to pay.
- 13 July 2016Abilities that reduce the cost of a spell apply after abilities that raise them. For example, Borrowed Malevolence with both modes chosen costs {1}{B} to cast if you control Voracious Reader.
- 13 July 2016If you activate Curious Homunculus's mana ability in response to its triggered ability, you can spend that mana to cast an instant spell during your upkeep after it has transformed into Voracious Reader. If you don't spend the mana, it will be lost before your draw step begins; you can't use it to cast the card you draw or to cast a sorcery.