Activate Woe Strider by sacrificing Ruthless Ripper
When Ruthless Ripper dies, Yedora triggers, returning Ruthless Ripper from your graveyard to the battlefield face down as a Forest land.
Resolve the Woe Strider ability
Activate Ruthless Ripper's morph ability by revealing a black card from your hand, turning it face up.
Repeat.
This clever loop exploits the quirky rules interaction between Yedora, Grave Gardener and face-down creatures to drain an opponent out of the game entirely. By using Woe Strider to sacrifice Ruthless Ripper, you trigger Yedora, Grave Gardener's static ability to immediately return that creature to the battlefield as a face-down Forest land. From there, you can pay Ruthless Ripper's morph cost to turn it face up, triggering its life-loss ability and resetting it so Woe Strider can sacrifice it all over again.