A warrior that refuses a challenge will invariably attempt to hide from the foe. Thus is their cowardice revealed to all as they hastily retreat into the rear ranks of their unit.
If the opposing player refuses to accept a challenge, the player that issued the challenge may nominate one of the characters or champions that could have accepted it. The nominated model must immediately 'retire' from combat. Upon retiring, the nominated model:
Moves through the ranks to take up a position away from the fighting rank.
Cannot make any attacks or have attacks directed against them.
Confers no benefits to the unit in the form of Leadership, special rules, or anything else.
Once a character or champion has been retired from combat in this way, they cannot return to the fighting rank whilst their unit is still engaged with the enemy model that issued the challenge – they are far too occupied with their cowardice!