Wheelbot

This creature gets +1/+0 for each instant and
sorcery card in your graveyard.
This creature gets +0/+1 for each other artifact
you control.
Whenever you cast an instant or sorcery spell,
you may search your library for a noncreature
artifact with lesser converted mana cost, reveal
it, and put it into your hand. If you do, shuffle
your library.