I love Aggron a lot, but I've always been fascinated by Lairon's design too. I also love the Steel/Fire combo, but don't really like Heatran, so I came up with this.
Another bit of trivia I have for it:
Living in the Grumbling Mountain, Lairon's new diet of obsidian and other igneous rocks led it to adapt a new form when evolving. Maguron uses its new Fire Type to propel itself with small eruptions, resulting in charges capable of destroying even the sturdier tanks. It's very territorial and attacks any trespasser head on, though encounters are rare as they live in in caves they dig by eating through the rock.
Hope it compares with the high standard Aggron holds, lmk what you think!
by Article_West