Potting soil is great as long as it has no fertilizers added into it. I personally use coconut fiber because it seems to have a better texture than soil and does not pack down as hard. I have even heard of some people who mix the two together. Soil from the outdoors would probably be bad because it'd contain all sorts of bugs and other things that you would not want living in your home.
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2.1 Ball pythons
1.0 Boa Constrictor Imperator
0.1 albino Cranwell's horned frog
1.0 bearded dragon
1.0 Tiger salamander
1.1 breeding Clawed frogs
1.0 black kittycat
3.1 Oscar cichlids