What is the technique for a cannon versus a lone elephant and a soldier?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws and is regression-tested against the official 110-diagram repetition casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it against the engine before publishing.
Direct answer
The cannon side generally holds real winning chances, provided the enemy soldier can be neutralised first. A single elephant defends only seven fixed points and cannot cover every approach to the palace alone, so an actively placed cannon with a workable screen can eventually create threats the elephant cannot answer by itself. The soldier is the main complication, since it can support the elephant or generate its own counter-threats if left alone.
Dealing with the soldier first
A soldier working together with the elephant can plug exactly the gap the elephant leaves open, so the cannon side's first practical task is usually restricting or trading off the soldier before pressing the attack, rather than trying to break through while both defenders are still coordinating.
Why the elephant alone is not enough
Once the soldier is neutralised, the lone elephant is defending against an active piece with a full board to manoeuvre on and only seven points of its own to cover. The cannon side should keep probing different approaches to the palace, since the elephant's coverage has real gaps that a patient attacker can eventually exploit.
Related questions
Is this an easier win than chariot versus elephant and soldier?
Generally harder, since the cannon needs a screen to make anything happen and the defending side has more chances to disrupt that screen than it would against a chariot.
Can the defender ever hold a draw here?
Yes, with accurate coordination between the elephant and soldier the position can sometimes be held, especially if the cannon side misplaces its screen.
.