There has been a number of awesome supergroups in the rock/metal world that have only managed to release one album. This shouldn't be too surprising, considering their busy schedules, but if they do get the time, fans would love to get a second album from any of the following:
1. Killer Be Killed - This group joins members of Soulfly, The Dillinger Escape Plan, Mastodon, etc. and metal fans were stoked when their debut self-titled album was released in 2014. There hasn't been any new music since, but they are planning to record a follow-up at some point.
2. The Damned Things - This group features members of Anthrax, Fall Out Boy, Every Time I Die, etc. and they have yet to release music since their rockin' debut "Ironiclast." However, a new EP is supposedly in the works, so stay tuned.
3. Axewound - This band contained members of Bullet For My Valentine, Cancer Bats, etc. and they released their debut album "Vultures" in 2012. The album is great buy for any metalhead, but unfortunately there was never a follow-up. Not much has been said about the band either, so here's to hoping they do something in the future.
4. Them Crooked Vultures - This band joins Foo Fighters, Queens Of The Stone Age, and Led Zeppelin members and they released their self-titled debut in 2009. Rock fans have been eager for a second album, but it has yet to come. Dave Grohl did mention that they have talked about reuniting though, so maybe we will get new material one day.
5. Serpentine Dominion, the extreme metal supergroup featuring members of Cannibal Corpse, Killswitch Engage, and The Black Dahlia Murder released their insane debut album last year, and fans already want more. Considering the album is still relatively new, it is hard to say when a follow-up may be recorded.