Cheapest priced copy (Zendikar Rising Promos): $2.49 at Card Kingdom, near mint, their price list as of .
Roiling Vortex 
Enchantment · Rare · Zendikar Rising · #156
At the beginning of each player's upkeep, this enchantment deals 1 damage to them.
Whenever a player casts a spell, if no mana was spent to cast that spell, this enchantment deals 5 damage to that player.
{R}: Your opponents can't gain life this turn.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
5 printings · $2.49 to $6.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Zendikar Rising Promos | 156p | Rare | $2.49 | $3.99 |
| Zendikar Rising Promos | 156s | Rare | — | $3.99 |
| Secret Lair Drop | 1958 | Rare | $3.49 | $6.49Out of stock |
| Zendikar Rising | 156 | Rare | $2.49 | $3.49 |
| Zendikar Rising | 352 | Rare | $2.49 | $3.99 |
3 rulings from Wizards of the Coast
- 25 September 2020An ability that triggers when a player casts a spell resolves before the spell that caused it to trigger. It resolves even if that spell is countered.
- 25 September 2020Activating Roiling Vortex’s last ability won’t undo any life gained before it resolved.
- 25 September 2020In a Two-Headed Giant game, Roiling Vortex’s first ability triggers twice during each team’s upkeep. Each instance deals 1 damage to one of the players on that team.