Opponents control a number of artifacts and/or enchantments equal to or greater than seven divided by the number of opponents you have, rounded up.
An opponent cannot block and kill Hellkite Charger or Dockside Extortionist.
Blade of Selves attached to Dockside Extortionist.
Steps
Declare Dockside Extortionist and Hellkite Charger as attackers, triggering Hellkite Charger and Dockside Extortionist's myriad ability.
Resolve the Dockside Extortionist trigger, creating at least one token copy of Dockside Extortionist that is tapped and attacking.
When the Dockside Extortionist token(s) enter the battlefield, they trigger, creating at least seven Treasure tokens.
Activate seven Treasure tokens by tapping and sacrificing them, adding ({5} magic symbol) ({R} magic symbol) ({R} magic symbol) .
Resolve the Hellkite Charger trigger from step 1, causing you to pay ({5} magic symbol) ({R} magic symbol) ({R} magic symbol) to untap all attacking creatures you control and to get an additional combat phase after this one.