There's an awful lot to unpack in God of War Ragnarok's free Valhalla DLC, from learning how to permanently increase Kratos' stats to figuring out which runic attacks and relics are best suited to the current run. For the most part, the expansion does a pretty good job of guiding the players on their journey, although there are one or two instances when they'll be exposed to brand-new mechanics long before the game is ready to explain them.