Chaos Knight, Light's Bane

Whenever Chaos Knight, Light's Bane is blocked you may pay {x}, where {x} is any number less than 4. for each mana paid, create a copy of Chaos Knight, Light's Bane tapped and attacking that same target. The
copies untap at the end of your end step.
They take double damage from all sources
and are exiled at the start of your next
upkeep.