Undercity InformerHow it works & interactions with other cards

What It Does

Undercity Informer features a repeatable activated ability. For one generic mana and the sacrifice of a creature, you target a player. That player must reveal cards from the top of their library one by one until they hit a land card. Once a land is revealed, all revealed cards—including that land—are placed directly into that player's graveyard.

How It Resolves Step-by-Step

First, you pay the cost: one mana and sacrificing a creature (which could be the Informer itself). Second, the ability is put on the stack and you choose a target player. When the ability resolves, the target player begins flipping cards from their library into a 'revealed' zone. This continues until a land card appears. Finally, all those revealed cards move to the graveyard simultaneously. If the player has no lands left in their deck, their entire library is revealed and moved to the graveyard.

Common Mistakes

A frequent misconception is that the land card stays on top of the library or goes to the hand; it does not. The land card that stops the process is included in the cards put into the graveyard. Additionally, remember that since the sacrifice is part of the cost, players cannot respond to the sacrifice itself to save the creature you are using for the Informer's ability.

When to Play It

This card is most effective when your opponent has manipulated the top of their library or when you are running a 'Oops! All Spells' style deck that lacks land cards entirely to mill yourself. It also serves as a great way to get 'dies' triggers from your other creatures while simultaneously putting pressure on the opponent's deck size.

Interaction examples

Maximizing Value with Simulacrum

Solemn Simulacrum

With both on the battlefield, you can pay {1} and sacrifice Solemn Simulacrum to Undercity Informer. This activates the Informer's ability to mill a player. Because Solemn Simulacrum died, its triggered ability also goes on the stack, allowing you to draw a card. You effectively mill your opponent and replace your creature with a fresh card from your deck.

Tribal Synergies

Roaming Throne

If you play Roaming Throne and choose 'Human' or 'Rogue', it will gain those types. Note that Undercity Informer has an 'activated ability' (identified by the colon), not a 'triggered ability' (which starts with When, Whenever, or At). Therefore, Roaming Throne will not cause Undercity Informer's mill effect to happen twice when you sacrifice a creature.

The Empty Deck Scenario

If you target a player who has already searched all their basic lands out of their deck, you might hit the ultimate payout. Per the official rulings, if the target player has no land cards remaining in their library, the Informer's ability will reveal their entire library and put every single card into their graveyard, likely winning you the game on their next draw step.