Equipped creature gets +2/-2 first strike and "Whenever this creature attacks, you may pay {1}. If you do, destroy target creature."

{2}: Double the power of equipped creature. Put a charge counter on Sword of Kas.

At the beginning of your end step, if equipped creature did not attack, put a charge counter on Sword of Kas.

If the Sword of Kas has four or more charge counters you lose the game.

Equip {3}