Ah, the iconic Gorillion! Awesome in its simplicity. The only card in any of the packs that has no keywords and no ability, because it doesn't need them! And the only card in the game that is 10 power out of the gate with no conditions (Lone Yeti) or drawbacks (Cursed Gorillion, Cave Lizard).
Power-wise, the only card in First Contact that can contest Gorillion by itself is Lone Yeti. Aside from that, Shield Bugs and/or Urchin Hurler may help some cards get to 10 or above. But without those in play, Gorillion will be the highest-powered creature in play.
Gorillion is at its strongest when the opponent doesn't have a Poisonous creature in play, as it would be free to attack. However, even if it can't attack (because of Poisonous, an Explosive Toad, etc.), it's still incredibly powerful as a wall. Not much can get by it, and it's a card your opponent may need to prioritize if they want to stand a chance.