Cheapest priced copy (Duskmourn: House of Horror Commander): $2.49 at Card Kingdom, near mint, their price list as of .
Monologue Tax 
Enchantment · Rare · Marvel Super Heroes Commander · #317
Whenever an opponent casts their second spell each turn, you create a Treasure token.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
8 printings · $2.49 to $7.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2021 | 19 | Rare | $3.49 | — |
| Commander 2021 | 346 | Rare | $7.99 | — |
| Duskmourn: House of Horror Commander | 100 | Rare | $2.49 | — |
| Marvel Super Heroes Commander | 139 | Rare | $2.49 | $2.99Out of stock |
| Marvel Super Heroes Commander | 317 | Rare | $3.49 | — |
| The List | C21-19 | Rare | $2.79 | — |
| Secret Lair Drop | 1838 | Rare | $2.99 | — |
| Secrets of Strixhaven Commander | 157 | Rare | $2.79 | — |
3 rulings from Wizards of the Coast
- 16 April 2021The ability can trigger once each turn for each opponent.
- 16 April 2021It doesn't matter if Monologue Tax was on the battlefield for the first spell. It also doesn't matter if that first spell resolved or not.
- 16 April 2021Nothing special happens on the third spell, fourth spell, and so on.