Meh, Sintax. They just re-use the engines ATLEAST 3 times.
Examples : Super Mario-esque Engine : Donkey Kong 5, Digimon Amethyst AND 2003 Digimom Sapphii (yes, Digi'mom' XD)
Buggy, Untested and Crappy Platformer Engine : Digimon Adventure, Spiderman 3, Rayman IV, Sonic 3 Fighter Sonic (seen that on eBay yesterday hah), Crash Bandicoot IV and Lord of the Rings 4.
Many more examples, but these were the ones that are at the top of my list.
And also, Makon Soft/Yong Yong is crap for platformers, but decent for fighting engines. Strange huh? :lol: