Chain Lightning

The wizard channels a torrent of lightning that leaps from foe to foe.
Chain Lightning has a casting value of 7. If successfully cast, pick an enemy unit within
24" of the caster that is visible to them. That unit suffers D3 mortal wounds. Then, roll a dice for each enemy unit within 3" of the first. On a 4+, that unit suffers 1 mortal wound.