|Full Name||Ztowser, the Undestroyable|
|Species||Ztar combination of Bowser|
|Main Weapon(s)||His spiky hair, his fists and his shell|
|Ability/ies||To change it's fists into weapons, make dark planets and use his spiky hair to hurt anything|
|Vulnerable To||Harming the Combination Ztar in the middle of his chest.|
|First Appearance||Super Mario Bros.: The Popstar Crossover|
|Latest Appearance||Super Mario Bros.: The Popstar Crossover|
Ztowser, hence the name, despite being a evil clone of Bowser, he looks like him, but different, having the looks of Dark Bowser but different, he is shadow colored with glowing red eyes, he also has no legs but also floats, unlike Dark Bowser, Combination Ztar is revealed inside his shell, which is his weakness (and heart).
It was created after the rage of the Combination Ztar after the defeat of Possessed Kirby, it created Dark Popstar and flew away to it, but Mario and the gang followed him to the planet, his palace was found on the Dark Popstar but many challenges awaits them, after completing the challenges, they encountered him and defeated him, releasing the Combination Ztar, and killing Ztowser in the process, Combination Ztar attacks the gang but also defeated it too, destroying the planet along with the dead remains of Ztowser, never seen for the rest of the game again.
- Despite being an evil clone of Bowser, it dosen't breath fire like the real Bowser and Dark Bowser does, but only puffs out smokes.