Yes, Hamletback Goliath is a rare creature from the all-hallowed set that is Lorwyn. Honestly, it’s not a terrible card. When he was reprinted in the Magic 2013 Core Set, the Goliath was a bomb in Draft, giving you something useful to Fling at your opponent for good game. I assume he was pretty good in Lorwyn draft, as well. But in Standard, he’s always been a big fatty that didn’t get any play.
Plenty of Commander players have found room for him over the years. A 6/6 that can get a lot bigger in a hurry is pretty good. It’s especially good that he gets as many +1/+1 counters for each and any creature that enters the battlefield, not just your own. This can obviously lead to him being bigger than anyone can stop.
But is he a good card? The decks that typically use him are after his overall power. Lovisa Coldeyes likes him because he’s a Warrior, and can give him +1/+1 and haste. Brion Stoutarm likes him around to Fling him with his ability - and gain 6 life in the process. Kalemne, Disciple of Iroas likes him for the experience counter casting him offers. (That and he actually was reprinted yet again in the same Commander 2015 deck as Kalemne, so why not?) A bunch of other Commanders will play him if they need to fill a hole in their list - more as a stopgap that opponents will have to consistently deal with rather than a long-term solution.
But there is actually a way to make this bulk-rare Goliath into an EDH win condition. How is that?
So which Commanders would be running both Red and Blue that would want to have this awesome sauce combo in their arsenal?
Animar, Soul of Elements is the first one that comes to mind. With Animar’s ability to reduce creature casting costs, you can reduce Goliath’s initial casting cost to as low as a single Red mana. (Notably, Rakdos, Lord of Riots can do this, as well, but being red & black only, no Rite of Replication trick is possible.) Surrak Dragonclaw is another, and he even gives all of your other creatures trample!
Both decks typically play Temur Ascendancy and/or Maelstrom Wanderer in their 99, both of which offer all creatures haste. Maelstrom Wanderer is another Commander that could use Hamletback Goliath, but he’s not really a great target for the Wanderer’s dual-Cascade ability - there are just a lot better things you’d want to hit. But in Animar and Surrak, you’re looking at two creature-based decks happy to send in a sextet of Goliaths in for the kill. Both decks are happy to play Rite of Replication to make copies of their other value creatures, so you’re going to have fair enough synergy for the Goliath to work.
(Ruhan the Fomori, a White/Red/Blue commander, has been known to be the head of Giant tribal decks on occasion. Hamletback Goliath fits that bill, but it’s rare that you’ll see Rite of Replication be a key card in that deck.)
It may seem strange to say that you can actually have Hamletback Goliath be part of a win condition. But it is, in fact, completely possible. So next time you wonder why Hamletback Goliath got a special promo release in Walmart repacks you’ve been able to find for years, it turns out he actually has an audience.