Spinner of Souls is a powerful Spider, with relatively weak defenses, compared to the average Spider
However, the first March of the Multitudes can be cast to give you enough lifelinking blockers to prolong the game, with the second or third pulling completely ahead of the opponent
It might feel like the only way to deal with something like that is to remove it immediately, which is only a short-term solution when dealing with someones commander
It provides both consistency and protection
Where The Lost Caverns of Ixalans main set primarily covers the expedition to the core of the world, The Lost Caverns Commander decks put the focus on the planes main factions and their typal synergy
But his Surprising Skill ability gives him Challenger +4 the turn he's played, so he's more like a 5 Strength Rush character