As we saw with 21 Savage's Savage Mode, working with Metro Boomin across an entire project can be very effective. If you've been following the Atlanta by way of Memphis producer throughout his ascendance over the last few years, you'll know that he's hinted at a number of other collaborative projects, though many have not seen the light of day. Today, we're revisiting a few of the projects the prolific producer has hinted at over the last few years -- from those that seem like they could drop any day now to those that feel forever doomed.

Click through the galleries to see the list, and let us know which of these projects you'd most like to see come to life.