Oh boy...lost snakes are oh so much fun...ok, enough with me being sarcastic
The baby powder is a good idea - I've also heard to use baking soda. Snakes like the edges of a room so look there. I've also heard to look up as they'll try to climb. You can try to invert the top half of a two liter and place a pinky inside to entice the snake to eat. You could also try putting a hide on top of a heating pad or some other source of heat. If you can stand it sit down there and listen at night - that's when they usually move around. It might give you some indication of where they are. You can try putting water bowls out as well with a hide right next to it and baking soda around it. I'd just be careful that you don't accidentally overlook the snake if your basement's anything like mine at home. Don't give up. We found Shadow over 2 weeks after he disappeared and he was not even 5 feet from where his tank had been. Most likely it's in a place close to the tank curled up. Good luck and let us know what happens.
~Katie
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2.4 Cornsnakes (Slink, Shadow, Suzie, Snickers, Selena, Sunshine)
0.1 Columbian Red Tail Boa (Baby)
0.3 Leopard Geckos (Cutie, Lily, and Miss Piggy)
0.1 Savannah Monitor (Sam)
0.2 Pac Man Frogs (Gordito and Spud)
0.1 Suriname Toad (Squishy & the Squishettes)
0.0.2 Giant Millipede (Mega & Mila)
0.0.1 Green Iguana (Iggy)
0.0.1 Red Eared Slider (Tiny)
lots of snails and fish...