I’ll second Christopher on the amp. I don’t think you’ll be able to get the “juice” or “jam” of a good saturated tube amp with pedals, unless you go for some high-end processors like a Helix or Fractal.
The other thing to think about is if you’re going for a tone for playing by yourself, or playing with a band (or recording multiple guitar tracks, bass, drums, etc).
When I play with my band, or if I’m recording a song, I’ll use a tone that has focused mids, low treble and low bass. It cuts through the mix. This tone though, by itself, doesn’t sound very metal. It sounds thin.
When I’m just practicing along to a metronome or drum track, I use a tone that has lots of bass, still more focused mids and I turn up the treble a bit, just to make it more pleasing to my ears.
So yeah, I’m guessing that wasn’t the answer you were looking for. If you just play by yourself, on the cheap side, you can go with a Boss GT-1 or Line 6 Firehawk. They are cool little multi-effects and with the proper amount of time put in to build a patch, you can get something sweet out of them. I think the Firehawk is bluetooth too, so you can tweek your patches with a mobile app.
Cheers