Monkey Puncher is a GameBoy Color game, released in late 2000, which relies on pretty much the same gimmick of the above games; you raise a monkey, you teach it stuff, and it battles other monkeys on the arena.
Story
The story of this game is very simple, and pretty much reminds me of old-school games a lot. You can choose from two siblings to play as - the one you don't pick gets kidnapped along with your own father, a renowned monkey trainer, by the Saru monkey gang, an evil gang that specializes on monkey fighting and mind control (???). Then, you get visited by some of your father's old friends and companions who give you a brand new monkey to train, Freddy the monkey, and set up your boxing matches. Only by beating opponents of a higher rank you may advance, and only by advancing you will be able to eventually confront the Saru gang master.
Look at the grin, masking his unseen but powerful hate.
There're some translation mistakes and not everything is worded properly, but if you overlook that you'll find it only adds to the charm of this old game. "Freddy looks happy. It must be happy." is only one of the great lines you will read in this game.
Gameplay
The basis of this game is monkey training, so that's mostly all you will be doing. You can raise the monkey's speed by skipping rope, or raise his power by punching a sandbag, or you can increase its intelligence by having him do your grocery! The way you train your monkey is unique and interesting: you have to show him how to do it first. That means you have to press A rhitmically to do various exercises, be them sit-ups, or running, or punching. As you go on the training gets more intense and harder to do, even for you - at a certain point, you have to do the double-jump skipping rope challenge, which means pressing A, and then pressing A twice real quickly while in the air to perform a double jump. The good thing, from a certain point on, the monkey will learn all of the training and will start doing it on its own, no rhytm A tapping needed.
Praise your monkey when he does well and you'll be sure to have a friendly and smart monkey
As for the boxing matches, you really can't do much but watch, give the monkey a strategy to go for ("Hit! Hit!") and heal your monkey in the break. Your monkey stats will dictate whether he wins or loses.
Freddy vs. Freddy?!
Training isn't all you do though; don't forget to feed your monkey! You can also mate your monkey with another monkey later, and the offspring will be more powerful than the parents. There are different types of monkeys, 5 types in total not counting special bosses I think. There's the cute lil monkey, the fat monkey, the cool ninja monkey, and so on. They all can have different colors.
Just feed the poor thing already :(
Graphics
What's with all the lightning, anyway?
Music
) you'll eventually turn it down because it's getting on your nerves. It's just stock music for the most part, I don't remember any particular piece being very memorable.Why Do You Take So Long To Get To The Conclusion Jesus Christ You're An Asshole And I'm Never Reading Your Reviews Again
Overall, this game doesn't really have much replay value. What it does have for it, though, is an addicting gameplay and charming graphics that will make you want to at least finish it, and if you liked it, even maybe try training another monkey. It's also worth noting that if you finish this game and never played Digimon World then you oughta give it a shot 
Hello, do you have any bananas in there?
I think it could do very well with a NDS remake and a few tweaks in gameplay.