Opacity is a great substitute for a blend tool. Just pick a color, make it very light, and blend it in with whichever colors you need (works best with colors similar to each other). That’s what i did for the jp novel t-rex’s neck
Yeah that gradient was one of the more challenging parts of the drawing, that and matching a darker color to outline the scales in that gradient. The opacity tool turned out to be very useful for that. And thanks!