Although not officially a monster, suspense is an excellent adversary. It can be easy for a Dungeon Master to fall into a routine of monsters, treasures, and role-playing. One way to inject some variety into a campaign is to have your party explore an abandoned castle or mansion. There is something exciting about exploring the castle or mansion and never knowing if something will be lurking around the next corner. It helps to not rush into a combat, but continually find empty room after empty room with trinkets and clues the only thing they discover.

You can further add to the suspense by the addition of puzzles that need to be solved with the trinkets and clues to unlock doors and chests to progress in the castle or mansion. Powerful characters can usually overcome monsters if they attack strategically, but what if the castle or mansion separates and isolates the characters one by one like an old horror movie. Suddenly the characters find themselves off balance and not sure how to proceed.

This poses an interesting challenge for the party. Instead of being challenged head on, they need to overcome challenges individually and somehow escape to rejoin their compatriots.

It also allows the Dungeon Master to hone their storytelling skills by weaving tales and painting pictures on how party members have been isolated or trapped while the rest of the party continues on. It also then places an interesting challenge for the party remaining.

Do they continue on? Do they try and find their party member that disappeared before their eyes? How do they prevent another party members from disappearing? Do they all stay together and join hands? Do they retrace their steps and try and find a way out leaving a party member abandoned?

Then as the suspense build and builds, a final confrontations awaits.

But are they up to the challenge of what has been hunting them all night?