Kamek is a magikoopa who took care of Bowser when this one was baby until Bowser got tired of him. From his first appearance on Yoshi’s Island, he became a recurring character in Mario’s games. He also appeared in the Comic Nintendo System media still helping Bowser, and there are those who believe that Kamek is the enemy of Yoshi as Bowser is Mario’s. Kamek had also appeared in Mario Party DS with his Library.
Blooper is an enemy squid that has appeared in Mario’s video games since Super Mario Bros.
Akitu is a species of turtle with spectacles that is always mounted on a flying cloud, its main weapon is the Spinys, orange turtles with peaks in the shell, and uses a fishing rod to hold things.
His first appearance was in Super Mario Bros. These characters have appeared in many games, sometimes as a neutral character or as an enemy. Their leader is Lakitu King of Super Mario Galaxy 2.
They are walking bombs with a rope mechanism that explode within a few seconds of being thrown. They debuted in Super Mario Bros. 2. They can be picked up and thrown at the enemies before they explode.
In the saga Paper Mario, they are described as very temperamental creatures, whose wick ignites when receiving the first damage and they launch to explode against Mario in case of surviving to such a first attack.
In the same saga, some members of the Bob-omb race, Bombette in the first part and Admiral Bombard in the second, become the allies of Mario, but usually are enemies. Their leader is the Big Bob-omb of Super Mario 64.
Wiggler is a caterpillar with a flower on the head that when you jump on it gets angry and turns red. His first appearance was in Super Mario World, as an obstacle and since then he has appeared in several Mario games and Mario sports games, sometimes as an obstacle. His last appearance was in Mario Power Tennis as an unlockable character.
The Bill Bullets are bullet-shaped characters with a malicious gaze that debuted in Super Mario Bros. They are fired by cannons at Mario’s sight or appear on certain levels fired at a random and continuous distance.
These are a few Nintendo Mario characters with the intention to hurt Mario and his allies while there are more threats to them.