Cheapest priced copy (Ixalan): $0.49 at Card Kingdom, near mint, their price list as of .
Ruin Raider 
Creature — Orc Pirate · 3/2 · Rare · Ixalan · #118
Raid — At the beginning of your end step, if you attacked this turn, reveal the top card of your library and put that card into your hand. You lose life equal to the card's mana value.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
3 printings · $0.49 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Ixalan Promos | 118p | Rare | $0.69 | $0.99 |
| Ixalan Promos | 118s | Rare | — | $0.99 |
| Ixalan | 118 | Rare | $0.49 | $0.49 |
6 rulings from Wizards of the Coast
- 29 September 2017The mana value of a split card, such as cards with aftermath from the Amonkhet block, is based on the combined mana cost of its two halves.
- 29 September 2017If the revealed card doesn't have a mana cost (because it's a land card, for example), its mana value is 0.
- 29 September 2017If the mana cost of the revealed card includes {X}, X is considered to be 0.
- 8 November 2024Some raid abilities trigger at the beginning of your end step. These abilities trigger if you attacked with a creature that turn, even if the permanent with that raid ability wasn't on the battlefield when you attacked.
- 8 November 2024Raid abilities care only that you attacked with a creature. It doesn't matter how many creatures you attacked with or which player, planeswalker, or battle those creatures attacked.
- 8 November 2024Raid abilities evaluate the entire turn to see if you attacked with a creature. That creature doesn't have to still be on the battlefield. Similarly, the player, planeswalker, or battle it attacked doesn't have to still be in the game or on the battlefield.