a1 School of Mathematics, University of Southampton, Highfield, Southampton SO17 1BJ, UK (http://www.maths.soton.ac.uk/staff/Bowditch/)
We show that in the game of angel and devil, played on the planar integer lattice, the angel of power 4 can evade the devil. This answers a question of Berlekamp, Conway and Guy. Independent proofs that work for the angel of power 2 have been given by Kloster and by Máthé.
(Received August 02 2006)
(Revised August 16 2006)