In September 2008, the pre-release a new Collectible card game (CCG) entered the gaming world named PK Cards. Created by PKXL Cards, Inc. ("PKXL"), a company located in the state of Ohio. PK's first series, titled The Broken Seal, was officially released to the public at the New York's Toy Fair in February 2009. PK Online followed in January 2010.
PK considers itself a second generation collectable card game for both innovations in game play and its unique integration of paper and web gaming environments.
 Joyce Greenholdt of Scrye Magazine wrote "The new entry in the Collectible card game field is PK Cards... Unlike the majority of CCG's we've seen the last year or so, PK Cards targets experienced gamers rather than newcomers: the rules and gameplay manage to be both more and less complex then Magic: the Gathering".
PKXL is unique in this industry in that they maintain their own print facility along with their development and marketing. PKXL Cards, Inc. was located at 9108 Tyler Boulevard in Mentor, Ohio. They purchased all of their own printing presses and automated packing machines. Low sales for PK Cards shut the company down in 2011.
The artists that have worked on PK Cards
- James A. Bandsuh
- Yoshinori Ikehara 
- Tim Switalski
- Robert J. Walland
- Mike Gustovich
- Billy Dallas Patton
- George Sukara
This creative group illustrated PK's first set, The Broken Seal, and is hard at work on its anticipated second series. Most call Northeast Ohio their home. With in-house production and on-site illustrative capability, the PK Team has created some of the industry's most attractive cards.
The PK Cards first set is made up of 366 collectible playing cards. The first release contained booster packs and 4 Core Decks: Red, Yellow, Blue, and Grey. The set included 7 card types used to play: Avatar, Power, Influence, Henchman, Ally, Champion, and Legend. Each of these cards came with four levels of rarity: Common, Uncommon, Rare, and Exotic.
- Avatar: the leader of your army. With his/her abilities this card works with other cards in the set to boost troop’s abilities.
- Power: This card represents an ancient relic or magical item to alter game play by way of improving troops or even changing some of the standard rules of play.
- Influences: This is a onetime use card it is in play only for one sortie, it is a magical card that helps your troops or hurts your opponents.
- Troops: 4 ranks of troop cards split into 5 element groups, Fire, Water, Earth, Metal, and Wood. These cards represent the warriors that are being sent into battle. These cards have abilities that come into effect when the card comes into play. Even though you can play any troop at any time, you have to keep your troops in rank in order to keep from receiving the penalties.
- Henchman: The lowest ranking of the troop cards, this card can be played without an out of rank penalty.
- Ally: Rank 2 of troop cards can be played at any time, but without a Henchman in the field (face up) played in a sortie before the Ally card will receive a minus 2 to both attack and defense.
- Champion: The 3rd rank of troop cards can be played at any time, but without a Henchman and an Ally (face up) played in sorties before the champion card will receive a minus 4 to both attack and defense.
- Legend: The highest ranking troop cards can be played at any time, but without Henchman, Ally, and Champion (face up) played in sorties before the Legend card will receive a minus 6 to both attack and defense.
 Gameplay is similar to Hearts with a War mechanic to break ties. Gameplay proceeds until someone wins 7 prestige. In the race to 7 wins you will have 7 sorties in which you get to play your hand to try to get the most wins tricks. Each sortie includes a draw step, then an opportunity to play Powers and Influences, then ending your turn with the play of your troop card. The winner is the person with the highest card value. Example: attacker has a card with a 6 attack vs. defender with a 7 Defense.
In the event of a tie, one card's element may trump the other. Troop cards have one of 5 elements: Water trumps Fire, Fire trumps Metal, Metal trumps Wood, Wood trumps Earth, and Earth trumps Water.
If there's still a tie, players "PK" by playing war with the top card of their decks, attacker using printed attack and defender using printed defense along with elements for trump. PK ties are broken by repeating PK.
The winner's troop enters the battle line upright; the loser's troop enters the battle line inverted. The winner leads the next sortie; lead person in each sortie is always the attacker. The person with the most upright cards in his/her battle line after the 7th sortie wins a Prestige point. After the 7th sortie, the battle lines are wiped and gameplay continues. The first to get 7 Prestige points wins.