Dexter’s Laboratory is an American animated series created by Genndy Tartakovsky about a boy genius named Dexter, who has a secret laboratory hidden behind a bookshelf in his bedroom. Various games were released to tie in with the series, all developed and produced by the now defunct publisher BAM! Entertainment. [Info from Wikipedia]
This Dexter project, know as “Robot Rumble” or “Extreme Robot Rumble” was going to be a brawl fighting game in which various home-made robots fought in small arenas, but it was never released. The game vanished when Bam Entertainment closed down. It seems that Robot Rumble was going to be developed with the help of N-Space. Only a few screenshots and concept arts remain from the project.
Thanks to Jay for the english corrections & to Celine for the contribution!