Dark Leo & Shredder in hand or on the battlefield or in the command zone.
Easy Prerequisites
An opponent cannot block
Dark Leo & Shredder if it's on the battlefield, or another creature you control otherwise.
Dark Leo & Shredder doesn't have summoning sickness if it's on the battlefield.
You control at least four Ninjas.
Mana Needed
({W} magic symbol) ({B} magic symbol) plus commander tax if applicable if
Dark Leo & Shredder isn't on the battlefield available.
Steps
Declare
Dark Leo & Shredder as an attacker if it's on the battlefield, or another creature you control otherwise.
If
Dark Leo & Shredder isn't on the battlefield, when the declared creature is unblocked, cast
Dark Leo & Shredder either from your hand or from the command zone for its sneak cost by paying ({W} magic symbol) ({B} magic symbol) plus commander tax if applicable and returning the unblocked attacker to your hand.
Deal combat damage using
Dark Leo & Shredder, triggering its second ability, creating a 1/1 Ninja creature token and causing the opponent to lose their entire life total due to
Bloodletter of Aclazotz.
Notes
You must control four Ninjas when
Dark Leo & Shredder deals combat damage. Notably, if it isn't on the battlefield, you must control five total Ninjas if the attacker you will be returning is a Ninja.