FoilHow it works & interactions with other cards

What Foil Does

At its core, Foil is a universal counterspell that can target any spell on the stack. While its standard mana cost is four mana, its defining feature is the ability to cast it for 'free' by discarding an Island card and one other card from your hand. This alternative cost makes it a powerful defensive tool in decks that can maintain a large hand size.

How it Resolves Step by Step

First, you choose to cast Foil and select a target spell. You then decide whether to pay the mana cost of {2}{U}{U} or use the alternative cost. If you choose the latter, you must discard one card with the 'Island' subtype and one additional card of any type as you cast it. Once the costs are paid and the spell is on the stack, players may respond. If Foil resolves, the target spell is countered and moved to its owner's graveyard.

Common Mistakes

The most frequent error involves the 'Island' requirement. You must discard a card that has the 'Island' card type; this includes basic Islands or non-basic lands with the Island subtype, but not just any land that produces blue mana. Additionally, remember that using the alternative cost still counts as casting a spell, so it can be countered by other spells like Fierce Guardianship.

When to Play It

Foil is best utilized in decks that can easily recover from card disadvantage. Because it requires discarding two cards to cast for free, it is often a 'disadvantageous' trade in terms of resources. Use it to protect a game-winning combo or to stop an opponent's threat when you have no mana available but plenty of cards to spare.

Interaction examples

Countering a Late Game Threat

You Find the Villains' Lair

Your opponent casts You Find the Villains' Lair to counter your win condition. Even though you are tapped out, you discard a basic Island and a redundant spell to cast Foil for its alternative cost. Foil counters their spell, ensuring your original play succeeds.

Free Protection for Commanders

Fierce Guardianship

In a multiplayer game, an opponent attempts to counter your commander with Fierce Guardianship. You respond by casting Foil, discarding two cards. Because Foil is a creature spell while on the stack, Fierce Guardianship cannot target it, but Foil can successfully target and counter the Guardianship.

Refilling After a Foil Cast

Frantic Search

After you have used Foil to protect your board, you may find yourself low on cards. You cast Frantic Search on your turn, drawing two new cards to replace the ones discarded for Foil, and untapping your lands to keep your mana ready for the next turn.