Splice GRIMSTONE and DEVIL HORNS to make GARGOYLE. GARGOYLE is in signs category. Better plant this and come back later, it takes some time. Received experience is a mystery. Keep an eye out for the exp counter. Hitting it will break it but you need to count the hits yourself. You get at least 1 seed back (maybe more!) from splicing GARGOYLE. Will you strike it rich? You just have to count the gems yourself. Will you get enough blocks to build something? You just have to find out yourself.