Sickle

The Sickle is a melee weapon that can hook onto walls (And currently literally anything that can be hit with it)

Hitting something with it will cause you to be hooked on to it and will not fall, jumping will cause you to be unhooked and will boost you up a bit and pressing W or A or S or D while hooked will also unhook you and boost you but slowly

Using the jump boost is better for climbing up walls and using the WASD boost is better for going across walls