Virtual play - chess problem concept

Virtual play

Definition

In chess composition, virtual play refers to hypothetical lines (threats and variations) that would occur if White made a tempting but incorrect first move (a “try”) or in the initial position’s Set play (if Black were to move first). These virtual lines do not occur after the actual key move; instead, the key intentionally changes or removes them. Virtual play is central to the aesthetic of many problems because it showcases planned ideas that are artfully “switched off” by the key, enabling new, contrasting Post-key play.

In over-the-board analysis, players sometimes use “virtual play” informally to mean “lines that would happen if we chose a different move order.” While practical players may speak this way, the term is most precise and widely used in the realm of the problemist and the chess composer.

How it is used in chess

• Composition design: Composers build rich “try-play” with elegant mates and continuations that entice solvers; the true key then changes the solution, replacing that virtual content with new thematic play.
• Solving: Spotting the most attractive try is part of the art; recognizing why it fails (a single precise refutation) reveals what was only “virtual.” The solver must then find the key that alters this landscape.
• Thematic construction: Virtual play interacts with classic themes such as Lacny, Zagoruiko, Grimshaw, and Novotny, where composers arrange cyclic changes or interference ideas between virtual (pre-key) and post-key phases.
• Practical analysis: Players and coaches may mention “virtual variations” when explaining candidate moves that would lead to a different tactical or strategic scenario—useful when discussing Engine eval lines and interpreting the CP bar.

Strategic and historical significance

Virtual play is a cornerstone of classical two-movers and threemovers, underpinning “change-of-play” concepts where pre-key and post-key continuations differ. From early 20th-century problem schools to modern compositions, problemists have celebrated the contrast between:

• Try-play (virtual play): beautifully arranged mates and continuations that fail to a single resource.
• Key-play (post-key play): fresh, often paradoxical content that only appears after the key.

Notably, cyclic themes like Lacny and Zagoruiko choreograph how mates (or defenses) rotate between virtual and actual phases, creating highly artistic “change” tasks. The solver’s journey—from admiring the try’s elegance to uncovering the key’s deeper logic—is a signature experience of composed chess.

Examples

Example 1: A two-mover with a strong try. Imagine a mate-in-two where White is poised to deliver mating nets on several Black defenses. The tempting try is 1. Qh5? with the idea that on 1... g6, 2. Qxe5#; on 1... Qe7, 2. Bxf7+ Qxf7 3. Qxf7# is set up in the background. However, a single cold shower—1... Bb4+!—refutes the try, and all those lines remain “virtual” (they never occur in the actual solution).

Now the key is a quiet waiting move such as 1. Qf3!, which changes the matrix: 1... g6 now loses to 2. Qxf7#, while 1... Qe7 is met by 2. Bb5+ c6 3. Bxc6+ with a discovered motif leading to mate in the designed problem. The earlier try-play (the virtual play) has been replaced by new post-key continuations.

• Virtual (pre-key) ideas: threats and mates after 1. Qh5? that look convincing but are never realized.
• Post-key play: new, corrected lines after 1. Qf3! that actually appear in the solution.

Example 2: Virtual play vs. set play. In some problems, the initial position’s Set play contains elegant mates “if Black moves first.” After the key, those set-play lines disappear, replaced by different continuations. The pre-key set play is therefore virtual: it demonstrates intentions and geometry that the key intentionally reconfigures.

Example 3 (OTB flavor, illustrative only): In an Italian Game, White might examine a tempting but inferior “try” that appears to win material—lines that only work if Black cooperates. These lines are “virtual” because after the correct first move, play takes a different course.

Sample mainline to visualize a typical skirmish where tempting tactics can appear and vanish with a different move order:

Commentary: After 6... Nf6 7. Ng5, White may “see” a virtual shot like Nxf7 that would work if Black erred; but precise defense (…d5, …Be7, …O-O) typically nullifies it. A different move order for White can erase these “virtual” tactics and lead to a more positional game.

Why composers love virtual play

• Contrast and deception: The try is beautiful yet wrong; the key rewires the position.
• Thematic depth: Perfect for cyclic-change tasks (e.g., Lacny, Zagoruiko) where mates rotate between virtual and actual phases.
• Economy and purity: Well-crafted virtual play avoids excess pieces, aligning with composition aesthetics like “economy of force.”

Common motifs paired with virtual play

• Interference themes: Grimshaw and Novotny ideas often appear in try-play and then reappear differently after the key.
• Defense removal and corrections: A try fails due to one precise defense; the key specifically corrects for it.
• Change of mates: The mates prepared in the try are replaced post-key, or vice versa (a hallmark of change-of-play tasks).
• Study-like ideas: While endgame Endgame study composers don’t use “virtual play” as a formal term, the notion of “if a different first move, then this line” is analogous in analysis.

Tips for solvers

1. Identify the try: What is the most convincing first move, and what mates or threats does it aim for?
2. Find the refutation: There is often exactly one defense that kills the try—spotting it reveals the virtual nature of the line.
3. Search for the key: Look for a quiet move that neutralizes the refutation and introduces fresh, accurate post-key play.
4. Track changes: Compare pre-key and post-key lines to appreciate the thematic “change of play.”

Interesting facts and anecdotes

• Virtual play sits at the heart of change-of-play themes. In a classic Lacny cycle, three mates rotate against three defenses between virtual and post-key phases.
• Some prize-winning two-movers are admired as much for their virtual play (beautiful but illusory tries) as for their actual solutions.
• Modern engines can “see” through tries instantly, but composers and solvers still value the human narrative: the seduction of the try and the elegance of the key.

Related terms

• Set play: Pre-key play if Black moves first; often treated as virtual play.
• Post-key play: The real solution content after the key.
• Try: A tempting but refuted first move that creates virtual play.
• Variation and Continuation: The specific lines composing both virtual and post-key play.
• Zugzwang: Many elegant keys are quiet moves that induce zugzwang, transforming virtual play into actual winning lines.
• Helpmate: The term “virtual play” is also discussed in helpmates when contrasting set-play and post-key cooperation.

Key takeaway

Virtual play is the artfully planned, hypothetical content in a chess problem—seductive try-play and set-play that the key purposefully transforms. Understanding virtual play enhances your appreciation of composition aesthetics and sharpens your solving skills, while offering a useful mental model for evaluating alternative move orders in practical chess.