Mana Geyser is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Add for each tapped land your opponents control.

Complete guide

Mana Geyser is a powerful sorcery that turns your opponents' resource usage into your own explosive mana advantage. By counting the number of tapped lands your rivals control, this card can generate massive amounts of red mana to fuel game-ending spells. It is a staple in multiplayer formats where the total number of tapped lands can often reach double digits.

What it Does

Mana Geyser is a mana production spell that scales based on the current state of the board. It checks how many lands your opponents control that are currently in the tapped state and gives you one red mana for each. Because it is a sorcery, you generally use it during your main phase to set up a massive follow-up play.

How it Resolves Step by Step

First, you cast Mana Geyser by paying three generic and two red mana. Upon resolution, the game checks all lands controlled by all opponents simultaneously. You count every land that is tapped, regardless of whether it is a basic or non-basic land. Finally, that total amount of red mana is added to your mana pool. This mana will stay in your pool until the end of the current phase.

Common Mistakes

A frequent error is forgetting that Mana Geyser only counts lands controlled by opponents, not your own tapped lands. Additionally, since it is a sorcery and not a mana ability, it uses the stack and can be responded to. If an opponent has a way to untap their lands in response to the spell, you will receive less mana when it finally resolves.

When to Play It

The best time to cast Mana Geyser is immediately after your opponents have finished their turns or spent their mana on spells, leaving their lands tapped. In a four-player game, if each opponent has five tapped lands, you could potentially net fifteen red mana for a single five-mana investment.

Interaction examples

Clearing the Board with Chain Reaction

Chain Reaction

If your opponents have many creatures and tapped lands, cast Mana Geyser first to generate a large amount of red mana. Use a portion of that mana to cast Chain Reaction. The Chain Reaction will then deal damage to every creature on the battlefield based on the total creature count, effectively using your opponents' land usage to fund their own board wipe.

Fueling a Massive Chandra's Ignition

Chandra's Ignition

After generating a surplus of red mana from Mana Geyser, you can cast a high-power creature and then use the remaining mana to cast Chandra's Ignition. Target your powerful creature to deal damage to all other creatures and all opponents. Mana Geyser provides the high cost required to play both a threat and this powerful sorcery in the same turn.

Guide written with AI from the official text and rulings. Official English text prevails.