From the website:
The kingdom of Astoria was suddenly thrown into a war. The hostile empire began the campaign to take the fertile lands for their own. The military strength of the empire was vast, the royal army was obliterated, and the capital of Astoria fell.
Only one member of the royal family, Cornelia is left. She was just sixteen, a small child with no knowledge of politics or military tactics. But she did not hesitate a second to devote her life to her youthful ideal of vengeance.
“I will fight to the bitter end for my people. It is true that this fight is nigh hopeless. Nonetheless, I call upon all of you who refuse to cast away your hope! Gather! Gather around our Unicorn Flag!”
Custom Heroes is a fast-paced, strategic game of set building and strategy. Similar to Diafugo (aka The Great Dalmuti, etc.) the objective of the game is to get rid of all your cards faster than your opponents. You can play sets of cards that have the same or greater value and the same number in the set as the previous player, but you have to balance the use of high value cards vs. the risk of getting stuck with low value cards in your hand as other players finish before you.
The twist in Custom Heroes is that as you play you earn and spend Power resources which allow you to Card Craft the cards in your hand by sliding upgrades into their sleeves that overlap the card and upgrades already present to alter the value and special abilities of your cards. As each round passes the cards become more and more valuable and complex!
Custom Heroes uses a clever system of winning victory points to determine who is the ultimate winner of the game and there is a wagering mechanic that can allow for wild swings and surprise come from behind victories.