FLIR ONE Pro Thermal Camera Review - Detect Invisible Problems In Your House 

The IR camera works well in the dark, we just lose the visual from the normal camera.

Yes, you can change the color pallete easily.

How about zoom?

yes, it can detect animals in total darkness. The larger the animal, the better the heat signature. Elk in a field will show upat a distance, but perhaps not a smaller animal. Also, the greater the heat difference, the more it will pop. A warm night, animals may not stick out that much. On a cold night, they will show a larger difference in temperatures and show up better. Cold blooded animals (snakes, etc) will not show up or have very little heat/thermal signature.

Ball bag