Knight, 'Guard':
This card should read, 'When a monster moves into an empty space adjacent to you, exhaust this card to interrupt that monster's activation and perform an attack with a Melee weapon. After this attack is resolved, if the monster was not defeated, it may continue its activation.'
Source: Official Errata
Q: If a condition is applied to an attack that uses Blast, do all figures affected by the attack suffer the condition?
A: Yes, but each figure affected by the attack still needs to be dealt at least 1 h (after its own defense roll) in order to suffer the condition
Source: Official Errata