My dog is crazy

So I have this little dachshund, that I simply adore, he is the craziest dog I have ever had, But this dog is nuts, hes not scared of anyone or anything ( except rain hes kind of a wuss when it comes to being wet and cold )He survived being bitten by a rattle snake, and thinks he runs the neighborhood of dogs. One day I look outside and there are a few deer in the yard, Wiener ( the dog ) was outside in the yard as well, and I'm thinking why are these deer not running away from the dog, all of the sudden one of the deer starts playing with Wiener, like charging then stopping then charging and they were taking turns! it was bizarre I don't think I've ever seen a deer play with a dog, so I watch for awhile then the deer finally charges and tramples Wiener, I freaked out and ran to his rescue, he was a little dazed but fine, not long after that, We were going to bed and I let the two dogs out ( I have a yoodle too ) and Pebbles ( the yoodle ) came back, while Wiener was around the corner barking and growling like a crazy mad dog, so I go out there with a flashlight and see that he has something cornered behind some 5 gallon buckets and a wall, its hissing and making gross noises, So I go over and see that it is a possum, the dog is obsessed with them, I have no idea why, so after trying to coaxe the dog away and watching him get bit, I finally get a piece of trim and block the possum and grab the dog and bring him into the house and survey the damage, he had a tiny bite mark by his eye but no harm or rabies and was fine the next day, then another time I had just got back from somewhere with my boyfriend Matt, as we are walking to the door we hear these awful growling and hissing noises coming from the woods, I knew at least one of the noises was Wiener, so we each are using our phones for light and we go check it out, We come to the edge of the woods and there is the dog and surprise a possum! They are squaring off then Wiener jumps on the possum and they start rolling around in the leaves biting and scratching, so I get a stick shove it between the two and pin the possum down, then Matt holds the stick on the possum and I grab the dog and once again save him (Although I don't know if I really saved him or the possum)I don't know, he thinks hes the biggest dog in the world, and that the whole forest is his and no one else is allowed in it. Hes crazy.