In a game proposed by J. H. Conway, a devil chases an angel on an infinite chessboard. At each move, the devil can eliminate one of the squares, and the angel
can make a leap in any direction, covering a distance of at most 
squares. Here, 
is a positive integer previously fixed, and is called the
"power" of the angel. The devil's aim is to trap the angel on an island
surrounded by a hole of width at least 
.
Can the angel indefinitely escape the devil, if his power is sufficiently high? Can the devil defeat an angel of any finite power? In 2006, Brian Bowditch proved that the 4-angel can win. Later that year, András Máthé proved the 2-angel will win, completely solving the problem.
