Tarfire on its own can't. With Relic it works, sure. But you have to blow a Relic and a Tarfire just to kill Goyf. If you have a Relic in play, often you can just attack with everything and ignore Goyfs. If they block, you can shrink them to 0/1s (unless opponent has an uncracked fetch or cheap instant to cast, and if you're worried about that you can just blow Relic postcombat to trade your dork with Goyf). I don't see this as a reason to play Tarfire. Once you start adding other cards, a lot of things can kill Goyf. Tarfire + Swords to Plowshares also kills Goyf!
Most importantly this tactic may not work on turn 2 to push Lackey through (the context of why to run Tarfires instead of some other removal). If you need to pop Relic, it's 3 mana total (Relic, Tarfire, activate). It only works if you only need to tap to exile your own Tarfire (e.g. just a fetch in their yard).