In Hidden Dimensions, the player controls a base capable of launching ships, deploying structures and performing actions.
Ships, structures and actions are represented by a deck of cards. Structures are your main source of energy, which is needed to play ships or perform actions. Ships can both defend your base or attack the ships or base of your opponent. Finally, actions, provide you with various ways of harming your opponent, defending yourself, modifying your ships and much more.
As players start the game for the first time, they'll be presented with a very short introduction in their first battle, additional and more detailed instructions are available in-game.
A series of achievements allow the player to unlock an additional 160 cards, bringing the total number of unique cards in the game to 232, divided over 8 sets (one for each of the alien races in Hidden Dimensions) and an extra set of relic and artifact cards.
The game features a semi-random deck generator, capable of generating thousands of unique decks built around the races their prime strategies. Premade decks are available and additional ones become unlocked through achievements. Finally, it's also possible to create your own decks.