From Jay: Jan's answer is my understanding of how the Crowd number and Bash strength work. It is up to you if you want to give examples. For ZT's animals, the Crowd number ranges from 10 to 100. There are several animals with 10. But the example I remember reading about was the okapi, which is at 10. The idea was that most of the okapi's fence should not be see through, so that it would rarely feel crowded. For ZT's animals, the Bash strength ranges from 0 to 325. There are 2 animals that have 325: Apatosaurus and Spinosaurus. Excluding zoo walls, tank walls, deteriorated fences, broken fences, and decorative fences, fence strengths range from 200 to 480. The one at 480 is the Electrified Chain-link Fence.