This series of trades has quickly become my favorite Marvel offering of the last few years. Vol. 4 collects the 4-issue Balder the Brave miniseries, and Thor #371-374 (NOT 371-373, as claimed by the back cover AND indicia).
Balder battles the Frost Giants, and Thor returns to Midgard after failing to find his father Odin in Hel (in vol. 3). Walt understands mythology so well, and uses it so effectively. Characters are bound by duty and their role in the grand tapestry, which often puts them at cross-purposes with what they truly want. Balder wants to stay with Karnilla, the Norn Queen, but duty to Thor and Asgard pulls him away (only to have tragedy befall the Norn Kingdom), and after returning and defeating the Giants, his duty once again takes him away from his heart.
Thor, who doesn't appear at all in the Balder series, is forced to balance a need to move on with his desire to find out the fate of Odin. Walt has Thor and a Judge Dredd-pastiche, Justice Peace, battle a probably-forgotten Thor foe (Zaniac, and gangster Thug Thatcher), before he spends an evening with the children of his former foreman (in his barely used Sigard Jarlson civilian ID), who give him back perspective. Gods finding themselves in the lives of mortals is a motif Walt's used again, in Orion when Orion is helped in Metropolis by a homeless veteran and a street-wise teenage girl. Different twists each time, but no less effective either time.
Then he gets drawn into the Mutant Massacre storyline, though Walt just tells it from Thor's perspective, and he just leaves X-Factor after saving Angel, so you really don't need to understand the big picture. Thor happened onto the scene when the Marauders are about to kill another hero (Angel), Thor saves him, reunites him with his allies, and then departs on his own adventure.
Great art from Buscema. His brother usually gets more love, but I've always preferred Sal's blocky, explosive artwork. He's dynamic, solid at character acting, and a terrific storyteller.
And points for the return of Puddlegulp, the frog!!