the figure 4 is the only trap that i have spent any amount of time studying and practicing...
this is partly because my interest in trapping is not that high, and partly because i feel that it is the most effective and versatile trap, as well as one of the easiest to make with nothing besides a cutting tool.
a fig. 4 deadfall can be set for a mouse or a deer, or anything in between. all you need are some sticks and something to cut with, and you have your trap.
also, since a deadfall is baited, it can be set anywhere. snares need to be set in places that animals typically walk. in the dryer seasons around here it can be tricky to track animals. instead of going to them, i can make them come to me. of course, setting a deadfall near an animal run will make it more convenient for the animal, and increase the chances for success, but in my opinion that is just icing on the cake.