Cheapest priced copy (New Capenna Commander): $0.49 at Card Kingdom, near mint, their price list as of .
Xander's Pact 
Sorcery · Rare · New Capenna Commander · #43
Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell.)
Each opponent exiles the top card of their library. You may cast spells from among those cards this turn. If you cast a spell this way, pay life equal to that spell's mana value rather than pay its mana cost.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
3 printings · $0.49 to $2.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| New Capenna Commander | 43 | Rare | $0.49 | — |
| New Capenna Commander | 144 | Rare | $0.49 | — |
| New Capenna Commander Promos | 43p | Rare | — | $2.49 |
6 rulings from Wizards of the Coast
- 29 April 2022If you pay the casualty cost of a spell, the copy will resolve before the original spell.
- 29 April 2022If you cast a spell for another cost “rather than pay its mana cost,” you can't choose to cast it for any alternative costs such as a blitz cost. You can, however, pay additional costs, such as a casualty cost. If the spell has any mandatory additional costs, those must be paid to cast it.
- 29 April 2022The copy of the spell is created on the stack, so it's not “cast.” Abilities that trigger when a player casts a spell won't trigger.
- 29 April 2022You may sacrifice only one creature to pay a spell's casualty cost, and you copy the spell only once.
- 29 April 2022Casualty N means “As an additional cost to cast this spell, you may sacrifice a creature with power N or greater.” and “When you cast this spell, if a casualty cost was paid for it, copy it. If the spell has any targets, you may choose new targets for the copy.”
- 29 April 2022If a spell has {X} in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.