Mathematics - PleaseHelpMe A shadow passes over the arid landscape. Scrubland-dwellers scurry to avoid the gaze of the flying beast and its rider. 0bb3lus the Undefined, dark sorcerer, returns to his Sinister Ziggurat* astride his fearsome wyvern, Skkraaa**.

* A ziggurat is massive pyramid-like building with successively receding levels. (Note: this illustration is not of 0bb3lus’s Sinister Ziggurat, which is much more sinister.)

** A wyvern is a winged, two-legged dragon with a barbed tail. (Note: this illustration is not of 0bb3lus’s fearsome wyvern, which is much more fearsome.)

Skkraaa lands in her nest on the middle level of the ziggurat. 0bb3lus dismounts and immediately goes up three levels to the laboratory where he drops off the potion supplies he bought at HexMart.

0bb3lus then goes down five levels to the nursery where he feeds the gremlins. Then he goes up six levels to the map room where he spends several hours planning world domination at the hands of his gremlin army.

Just before bed, he goes down ten levels to the ground floor of the ziggurat where he double-checks that the entry portcullis is locked for the night.

Finally, he goes to the top floor, polishes the lenses on the telescope in the observatory, and crawls into his sarcophagus for a nap.

How many levels does the Sinister Ziggurat have?

* A ziggurat is massive pyramid-like building with successively receding levels.

** A wyvern is a winged, two-legged dragon with a barbed tail.