Snake Eyes is an epic pirate unit that can replace your entire hand when played. Upgrading it will increase its strength and the number of cards drawn. Snake Eyes can fit into any deck that can make use of its hand cycling effect.
Snake Eyes' effect can be used to get rid of a useless hand and replace it with fresh options.
Note that Snake Eyes doesn't necessarily have to be played first in order to trigger its ability. Freebooters can allow you to play some cards before playing Snake Eyes.
Provided you have enough mana, this can be a great way to play important cards in your hand first to avoid Snake Eyes discarding them.
Using Snake Eyes, you can cycle through your deck faster. This can be useful for cards that would benefit from being played more frequently, like cards that deal damage to the enemy base or Olf the Hammer.
Don't be afraid to play Snake Eyes without activating its ability. It still has a very decent amount of strength.