Fetid Pools 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 or .) This land enters tapped. Cycling (, Discard this card: Draw a card.)

Complete guide

Fetid Pools is a versatile land that provides both blue and black mana while ensuring your hand stays fresh late in the game. As a dual land with basic land types, it offers excellent color fixing for Dimir mages and graveyard synergies alike. This guide explores how to maximize its utility through cycling and efficient mana management.

What it does

Fetid Pools is a nonbasic land with the subtypes Island and Swamp. It enters the battlefield tapped, meaning you cannot use it for mana the turn you play it. However, it possesses the Cycling ability, allowing you to pay two generic mana and discard it from your hand to draw a new card if you don't need the land drop.

How it resolves step by step

When you play Fetid Pools as your land for the turn, its replacement effect causes it to enter the battlefield tapped. If you choose to use its Cycling ability, you first pay the {2} mana cost and discard the card as a cost to activate the ability. The ability then goes on the stack; once it resolves, you draw one card. Because it is an activated ability, it can be responded to, but the discard happens immediately as part of the cost.

Common Mistakes

A frequent error is forgetting that Fetid Pools has basic land types despite not being a basic land. While it can be searched for by cards that look for an 'Island' or 'Swamp', it does not count as a 'Basic Land' for effects that specifically require that supertype. Additionally, remember that Cycling is an activated ability that functions only while the card is in your hand.

When to play it

Play Fetid Pools early if you have an opening in your curve and need the color fixing for future turns. In the late game, if you already have enough mana sources, it is usually better to use the Cycling ability to dig through your library for threats or answers rather than playing it as your land for the turn.

Interaction examples

Mana Fixing with Command Tower

Command Tower

If you are playing a Commander deck with blue and black, having Fetid Pools on the battlefield ensures your Command Tower can produce either color. While Command Tower checks your commander's identity, Fetid Pools provides the specific mana needed for intensive costs like {U}{U} or {B}{B}.

Enabling Opponents with Exotic Orchard

Exotic Orchard

If you control Fetid Pools, an opponent who controls Exotic Orchard can tap their land for either Blue or Black mana. This is because Exotic Orchard checks what colors your lands could produce, and Fetid Pools explicitly produces {U} or {B}.

Cycling for Answers

During your opponent's end step, if you have two mana available and no need for an additional tapped land, you can pay {2} and discard Fetid Pools. This allows you to draw a card, potentially finding an interaction spell for your upcoming turn without using your normal draw step.

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