Orion has finished plans for terraforming Mars. The Venus terraformer is gone because venus is gone, so they are trying it out on Mars.
It will input breathable gasses instead of converting the existing atmosphere, as Mars' atmosphere is thin. Then greenhouse gases, such as Carbon Dioxide, will be imported to increase the temperatures to suitable levels. Clouds should appear as water is introduced and some of the ice on Mars melts.
It is predicted with our current technology that this should be done by 150 years, however it could be done faster as technology advances.