I built the concept of the Oddball game mode in Halo into Dota 2. Currently version 1 is finished and up on the workshop. It was recently mentioned in a Join Dota post which can be found here: http://www.joindota.com/en/news/29761-custom-gamer-1-have-a-break-great-maps-that-take-15-mins-or-less
Also here is a link to the Workshop page: http://steamcommunity.com/sharedfiles/filedetails/?id=471491344
There are a couple of more things i would like to implement before i really think it'll be done:
More detail in the terrain
More varieties of buffs from pads and creeps
If you have any questions, comments or suggestions let me know here and i'll address them! Thanks!