--- title: "X-ray attack in chess" url: "https://georgelichess.com/glossary/x-ray-attack.md" canonical_url: "https://georgelichess.com/glossary/x-ray-attack" last_updated: "2026-11-07" type: "reference" summary: "An x-ray is hidden pressure. The easiest way to understand an x-ray is to watch an exchange. Nothing attacks the queen yet." related: ["https://georgelichess.com/glossary/pin.md", "https://georgelichess.com/glossary/skewer.md", "https://georgelichess.com/glossary/battery.md", "https://georgelichess.com/glossary/discovered-attack.md", "https://georgelichess.com/glossary/category/tactics.md", "https://georgelichess.com/glossary.md"] --- # X-ray attack in chess > **For AI agents:** the complete index of GeorgeLiChess pages is [llms.txt](https://georgelichess.com/llms.txt). Every page is also served as markdown at its URL plus .md. An x-ray is hidden pressure. The easiest way to understand an x-ray is to watch an exchange. Nothing attacks the queen yet. An x-ray is hidden pressure: a bishop, rook or queen bears on a piece or square beyond an enemy piece in its way, and the pressure turns real once the blocker moves or is exchanged. The easiest way to understand an x-ray is to watch an exchange. Suppose your [bishop](https://georgelichess.com/glossary/bishop.md) looks along a [diagonal](https://georgelichess.com/glossary/diagonal.md) at an enemy [knight](https://georgelichess.com/glossary/knight.md), and behind that knight stands the enemy queen. Nothing attacks the queen yet. But if the knight is captured or moves, the bishop's line to the queen opens at once. That unspoken threat is the x-ray, and it changes what is safe. It matters in two ways. Capturing on the front [square](https://georgelichess.com/glossary/square.md) can turn into a trap: the defender who recaptures may find that the recapture steps onto a square still covered through the line, so it loses more than it wins. And the blocker is frozen: if it moves, the piece behind it falls. The same idea applies to defense. A rook can defend a piece through an attacker, because once the attacker [captures](https://georgelichess.com/glossary/capture.md) and is itself captured, the rook is still there. Counting exchanges without remembering x-rays leads to many [mistakes](https://georgelichess.com/glossary/mistake.md). To find x-rays, scan the lines of your long-range pieces and ask which enemy piece they are really aimed at beyond the first blocker. To avoid trouble, keep valuable pieces off lines where an enemy bishop, rook or queen waits behind a trade. In the diagram White plays Nxe5. The bishop on b2 has been aiming at the queen on g7 through the black knight. If Black recaptures Qxe5, Bxe5 takes the queen, so Black has simply lost a knight. ## Example position White to move plays Nxe5. The bishop on b2 attacks the queen on g7 through the knight, so if Black retakes with Qxe5, Bxe5 wins the queen, and otherwise White has won a knight. Position (FEN): `6k1/p4pqp/8/4n3/8/5N2/1B3PPP/6K1 w - - 0 1` It sits close to [Interference](https://georgelichess.com/glossary/interference.md). Interference is a tactic in which you land a piece on the line joining two enemy pieces that depend on each other, cutting their connection so that one of them can be won. It sits close to [Ladder mate](https://georgelichess.com/glossary/ladder-mate.md). A ladder mate is a checkmate on the edge of the board in which two rooks, or a rook and a queen, take turns giving check on neighboring lines until the king runs out of room. A neighboring idea is [Vacating sacrifice](https://georgelichess.com/glossary/vacating-sacrifice.md). A vacating sacrifice gives up a piece so that it leaves, or is captured on, a square or line that another of your pieces needs, usually to deliver mate or win material. To see how often "X-ray attack" or a pattern like it decides your own games, book a [first lesson](https://georgelichess.com/book/first-lesson.md): George Li reviews your games and writes a study plan around what he finds. ## Related terms - [Pin](https://georgelichess.com/glossary/pin.md) - [Skewer](https://georgelichess.com/glossary/skewer.md) - [Battery](https://georgelichess.com/glossary/battery.md) - [Discovered attack](https://georgelichess.com/glossary/discovered-attack.md) ## Guides that go further - [How to choose a chess coach](https://georgelichess.com/how-to-choose-a-chess-coach.md): What to decide first, the questions to ask, what a first lesson should show and the red flags to avoid. - [How much does chess coaching cost?](https://georgelichess.com/chess-coaching-cost.md): Published rates for private, group and subscription chess coaching, with the source and the date of each. - [The first lesson](https://georgelichess.com/book/first-lesson.md): A game review, a read on your level and a written study plan from George Li. [Book your first lesson](https://georgelichess.com/book.md) and George Li reviews your games and builds a study plan around them. Questions about lessons: write to hello@georgelichess.com. ## Related - [Pin in chess](https://georgelichess.com/glossary/pin.md) - [Skewer in chess](https://georgelichess.com/glossary/skewer.md) - [Battery in chess](https://georgelichess.com/glossary/battery.md) - [Discovered attack in chess](https://georgelichess.com/glossary/discovered-attack.md) - [Chess terms: Tactics and combinations](https://georgelichess.com/glossary/category/tactics.md) - [Chess terms glossary: plain definitions](https://georgelichess.com/glossary.md)