Nightmares

Enter a world where the things that go bump in the night aren't just a figment of your imagination. They're lurking just beyond what we can perceive, waiting for their chance to pull you under. Welcome to Nightmares, the combination of a traditional Collectible Card Game (CCG) and a Roguelike Deckbuilder with a dark twist. 

Start by building a deck from your collection, just like you would in any CCG. Choose one of the four realms available in Nightmares to build your deck around. 
The Abyss 
Down in the depths of the ocean lies the Abyss. This realm consists of the nightmarish aquatic creatures that lurk in the depths and the inhabitants of the lost city that lies at the bottom of the Abyss, including Cultists, Necromancers, undead and the great Cthulhu. 
The Void
A realm that never stopped burning. Flames continuing to rise ever higher, and the screams of those within are never ceasing. The Void is inhabited by vicious demons and wild elementals driven mad by the forces they're made of.
The Black Forest
Horrible things await you in the depths of the Black Forest. So deep that the branches restrict all light. Where the trees come to life with malicious intent and there are spiders larger than a man. 
The Silence
The Silence is widely considered the most disturbing of the realms. It doesn't occupy a physical space but rather exists in the silent moments in the middle of the night when we all feel most on edge. The realm itself is consumed in true blackness, void of any light and its inhabitants are twisted beings made of shadow and hungry for blood. 

You can queue up any of the decks you've created in either story mode or PvP. Starting a game with a deck "locks it in" for a run. Once locked in, the deck can no longer be modified in the Deck Builder and it is given three lives. When these lives run out the run will end, the deck will revert to its original state (removing any upgrades you give it during the run) and you will be able to modify it again.

After each game, win or lose,  you'll get the opportunity to upgrade your deck to make it even more powerful. 
Upgrade Options For The Victorious
After each win you'll get to choose between upgrading a card in your deck to a more powerful version, adding an additional copy of an existing card to the deck, or removing a copy of a card from the deck.

Each upgrade has a significant impact on the power level of the individual cards in your deck, some can even unlock new synergies and strategies. 

Treasures For The Defeated
After each loss you'll get to choose one of several treasures to add to your deck. Treasures are extremely powerful cards that can only be accessed this way.

Can you craft the perfect deck and go on an undefeated run?