The Sentry is a main quest in Act II of The Witcher, taking Geralt out to the Golem Burial Ground in the swamp. Kalkstein needs ten sephirot to open the sealed Mage’s tower, and they only have eight. The ninth is lodged inside a stone golem known as the Sentry. Vaska tells Geralt what she knows about the tower and hands him a Tarot card that hints at how to beat the thing.
The trick is lightning. Geralt needs a lightning rod from a blacksmith and a storm overhead, then a careful dance between three stone posts so the golem gets fried and he does not. The druids will happily summon a storm for a fee, but any old rain shower does the job for free, so patience pays here. Once the golem crumbles, Geralt can cut the sephirah out of its remains.
