One giant redwood. Climb it to the summit.
Left click left hand · Right click right hand. Hold to grip, release to let go.
Mouse moves your free hand. With both hands gripping, pull the mouse down to haul yourself up.
Lunge: pull up fast with both hands, let go of both buttons, then grab again mid-air.
Space places a safety hook. You carry 3 hooks. Every 50 m of new height you get 3 fresh hooks; the ones you placed below stay in the trunk. Each hook holds up to 11 m of free fall (you fall twice as far as you are above it). More than that and it rips out, but it nearly stops you; then you fall to the next hook down. Hook every 5 m or less and the next one catches you.
If you end up hanging on the rope, grab the trunk again. R restart · Esc pause
The clock starts the first time a fork bites into the tree. Hit the ground and the run is over: you start again from the bottom.
Pale smooth bark won't hold · Charred bark slides and crumbles in your hand · Grey branches snap · Under burls your feet can't find footing.
Branches are solid. Climb around them or pull yourself on top and rest there. A branch below you catches a fall.