  In this paper, we study the time required for a {\lambda}-biased
({\lambda}>1) walk to visit all the vertices of a supercritical Galton-Watson
tree up to generation n. Inspired by the extremal landscape approach in
[Cortines, Louidor, Saglietti 2018] for the simple random walk on binary trees,
we establish the scaling limit of the cover time in the biased setting.
