Stoncryst is a Petrosapiens born in Petropia who had resided himself on DGC1927 before Petropia exploded, and appeared in Back To Earth having a counterfeit Omnitrix and used it to fight against the alien invaders on Earth.
Stoncryst's family had moved to DGC1927 and when he grew up he became a criminal, which earned him enough to get his own counterfeit Omnitrix to use. But it cost him prison time. However, he had been freed and is on parole, and swore to help others instead of doing bad.
Stoncryst was on Earth, touring around, when suddenly alien invaders on Earth appeared while Ben was gone. So Stoncryst had helped Drake, Robert and later Ben fight against them. It turns out the alien invaders want Stoncryst and that the alien invaders were alien law enforcers who wanted to arrest Stoncryst and put Earth on hold for mistaking that Stoncryst destroyed an inhabited planet and got Earth's help on destroying it. In reality, Stoncryst had been framed up by one of his friends in prison who had also been in parole. Stoncryst had later been freed and now helps fight against alien villains. He has not reappeared so far.
Aside from his powers being a Petrosapiens, Stoncryst can also transform into aliens, though in his case whenever he transforms he get weaker when he reverts to his old form. It also takes only around 5 minutes or less before he reverts back, although he can transform into another alien immediately after a previous one. The aliens he had used are:
- a Tetramand
- a Vulpimancer
- a Brightnesian
- a Zeimbean
- a Spheroid
- Back To Earth
- Datriyo Returns (working title; speculation)
- Stoncryst's Omnitrix resembles the alternate Ben 10,000's Omnitrix somewhat.