Runebinder

Deadly - Units and spells with Deadly kill any unit they damage, regardless of health. For example, a 1/1 with Deadly can kill a 5/5 attacker.

Lifesteal - Units and spells with Lifesteal give you health when they deal damage, healing you equal to the damage dealt.

Contract - You may pay the number in additional power to get its bonus. If you don’t have enough power to pay some or all of the Contract, the remaining balance is applied as “debt” that is paid at the start of the next turn.

Debt - Your available power is spent to pay off Debt. If you can't pay it all, you pay at the start of your next turn.