Master Mantis is the oldest employee of WarioWare and a former member of the Furious Five, a group of Kung Fu Masters from China who fought against Tai Lung, Lord Shen, and Kai (not The Chameleon though, because you know, she is a predator of insects like mantises), but always lost to Po.
Life[]
Master Mantis was born a mantis. Like all mantises, his family was very religious, so all he learnt from them was praying and praying.
When he was 6 months old, he knew he could not live any longer (alas the lifespan of his species), so he went to learn Kung Fu to gain immortality, and became one of the members of the Furious Five, along with Master Tigress, Master Viper, Master Monkey and Master Crane, under the mentor of Master Shifu. Po, on the other hand, sought revenge on the Furious Five so she "joined" and would later betray them. Po was so talented in martial arts so that the Furious Five's fights against various enemies were shams, in which they were all free riders just because of Po.
After three battles, Po managed to force Mantis to marry another mantis. Fearing that the female mantis would eat his head (just like other mantises), Mantis fled all the way off to North Korea, where he met Wario and decided to join him. Wario then used the Wa-Machine 2.0 to turn his species into human, and now he remained the same looks.
Some years later, a Kung Fu fanatic named Young Cricket got hired into WarioWare. He followed Mantis as his first (and only) apprentice.