Hasbro frequently releases Marvel Legends action figures based on characters from various Marvel Comics storylines and media adaptations, including characters from Disney+ shows like "WandaVision," "The Falcon and The Winter Soldier," "Loki," and more.
"The Watcher" refers to Uatu the Watcher, a cosmic being in Marvel Comics who observes and records significant events across the universe. Uatu is known for his distinct appearance with a large bald head and wearing a robe.
A "BAF" stands for Build-A-Figure, which means that this action figure set would have included individual figures of various characters, and collecting all figures in the wave allows you to assemble the larger Build-A-Figure, in this case, The Watcher.
Hasbro Disney+ Marvel Legends Wave 2 Set of 7