Total Mayhem takes Total Annihilation, bugfixes and extends it the way Cavedog might have. Early game pace is quicker, many new units added (longtime players may recognise some 3rd-party units), including a whole new 3rd tech level tier. Existing and added units have been bugfixed, rebalanced, re-modeled, re-textured and re-rendered to equal or exceed the standard of the original TA units.
There's an advanced geo in the current version, but you have to remove the regular one to build the new one. Not any more. Thanks to Idec's ingenuity and Rime's wizardry. I know how much went into this, so I'm very excited about this. I hope you're at least pleased.