As far as the archetype goes, I'm not sure if Goblins would actually be good. The strength of Legacy Goblins is the
Goblin Matron
tutoring and
Goblin Ringleader
's card advantage. Plus, it also has
Goblin Lackey
to act as another way to cheat goblins into play, plus
Rishadan Port
and
Wasteland
to tempo the opponent out of the game.
This particular build is not very good. Koth and Bolt are flat out terrible. Krenko's Command is really bad too (you want an actual Goblin). You've got Goblin Guide listed twice.
I'd look to add in
Mogg War Marshal
,
Goblin King
,
Stingscourger
, and possibly some of the other color goblins like
Wort, Boggart Auntie
. If you absolutely must play spells,
Goblin Grenade
and
Warren Weirding
would be the only ones I'd consider, though Weirding would require
fetch
lands
and
Blood Crypt
s.