Pretty simple request, I'm looking for metal bands that consistently use a piano. Could be a trad metal band, could be thrash, either would work.

Any help would be appreciated.

Savatage uses piano in many of their songs as far as I know.

Savatage - Gutter Ballet

Savatage's gutter ballet, streets, etc. albums.

a greek band named Swan Christy actually wrote all their songs on the piano/keyboard and then wrote riffs and stuff round that, so they're even more piano-driven. needless to say, they were mainly influenced by Savatage

Well some of those also have a synt sound but you should check them out anyways: Europe,Dream Theater, Savatage,Star One,Deep Purple, Rainbow, The Grace Under Pressure album by Rush, Javan, Stratovarius, Uriah Heep, Virgin Steelee, Pretty Maids,

One album you can check out that has some very heartfelt piano in it is Somewhere Along Our Memory by Sadness. The band is DSBM, but on this album the songs "Her" and "Kiss In October" are piano oriented, with riffs coming and going throughout. I can't really speak for the rest of their discography though. And I second the other user who mentioned them already: a lot of Virgin Steele's work is worth checking out for their piano usage as well.