Cavemen are a semi-common enemy throughout the game. They can be found sometimes in Areas 1 and 2 and they're common in Area 4 .
Statistics
H. neanderthalensis in its native habitat.
Normal Caveman
Health: 3
Size: Small (1x1)
Corpseable?: Yes
Stunnable?: Yes
Strategy
Cavemen can present a unique challenge to players first exploring the early areas of the game. Unlike all other area 1 enemies (other than the giant spider), cavemen are not necessarily killed in a single hit; instead, if you jump on them or whip them they will be stunned for several seconds. During this period they will be immune to further jumping or whip damage, meaning that a total of 3 rounds of such attacks will be necessary to kill them. Accordingly, it is often easiest to simply stun a caveman and move past him, just be sure to get an intuitive sense of how long you have before they wake up. Being ambushed by a just-awakened caveman can be an easy way to lose a life point or two. However, cavemen can be killed instantly by many other attacks, including pistol bullets, shotgun bullets and spiked shoe-enabled jumps, as well as by environmental hazards such as spikes, lava and man-eating plants. The caveman's stun period can be used to capitalize on these latter weaknesses, throwing a stunned caveman into a dangerous situation can serve to deal with it permanently.
The other unusual characteristic of cavemen is that when they see you, they enter an "aggro" mode, which causes them to move much more quickly. Luckily, the game calculates a caveman's sight in a very narrow way: they can only see you if you are standing on the same vertical level as they are, in the direction they are facing, and within 6 tiles. Therefore, there are plenty of places that might seem dangerous, but that are safe according to these rules.
You can release a Frozen Caveman with a bomb or mattock, but why would you want to?
A caveman normally moves slowly, walking a few tiles, pausing, and then walking a bit more. When they encounter a low wall, they will sometimes jump. When they enter their aggro mode though, they begin to move much more quickly, and tend to keep running in a given direction until they hit an obstacle. In this mode, it can be tricky to time your jump to land on them, or your whip attack to hit them before they hit you. Therefore, the ideal plan is to sneak up on cavemen and stun or kill them before they ever see you.
Also note that a stunned caveman always wakes up in normal, non-aggro mode, regardless of its state before being stunned.
In Area 3, cavemen can be found encased in ice . They will spawn normally in all other areas.
An easy way to deal with cavemen can be to stun them and throw them into a natural (non web-gun) web. They will remain stunned permanently, unless the player decides to pick them up and throw them around. Everyone has hobbies.