Hellkite Charger and Nature's Will on the battlefield.
Lands you control can tap to produce at least ({5} magic symbol) ({R} magic symbol) ({R} magic symbol) .
An opponent cannot block Hellkite Charger.
Steps
Declare Hellkite Charger as an attacker, triggering its ability.
Holding priority, activate all mana-producing lands you control by tapping them, adding at least ({5} magic symbol) ({R} magic symbol) ({R} magic symbol) .
Resolve the Hellkite Charger trigger, 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.
Deal combat damage to an opponent using Hellkite Charger.
Nature's Will triggers, tapping all lands the defending opponent controls and untapping all lands you control.