The battles are a card-based combat format, the player can choose three units and a support to battle, it also can use one unit borrowed of other player. In battle, the player has to choose three of the several skills of their warriors to attack the foe, such as cause damage, apply a negative status the enemies, boost or heal your allies or just combine cards in order to use a more powerful attack, and then, when the Ultimate Gauge is completed, the unit can use its Ultimate move.
The story mode is based on the anime events in a resumed version, it currently has the full Holy Knights saga and major part of the Ten Commandaments saga's arc with further arcs, special events and game's original arcs, and side stories being added in further updates, such as a collaboration with That Time I Got Reincarnated as a Slime franchise as the first chapters of the Disasters' arc.
In order to get new units, the player has to summon in a banner with the chance of getting random characters except limited time characters, only summonable during the event period. Expending 3 Gems the player can get one random unit, with 30 gems, it can get a multi summoning of ten random units, if it multi summons for 5 times without pulling any SSR unit, the next one will have a guaranteed SSR unit on it. In other occasions, there's the step-up banners wich only allows 30 diamonds summons. There as more as you summon, you'll be given rewards, including the banner's main character
Some units, however, can be obtained after finishing some story arc levels.
It was released on June 9, 2019 in both Japan and Korea while in the rest of the world it was released on March 3, 2020.
The Seven Deadly Sins: Grand Cross provides examples of:
- Absurdly High Level Cap: The maximum level of a unit is 60 when it reaches UR and in order to reach to level 80, a player must do Death Matches with a boss monster which contains Red Demon Horns, Grey Demon Wings, and Crimson Demon Ears.
- Arbitrary Headcount Limit: Each party is composed of 4 members. 3 in the main team and 1 in the sub as backup.
- Big Bad: Lilia, a former student of Merlin turned bad, is shaping up to be this.
- Boring, but Practical:
- The R units. They may have weaker stats and skills, but they were cheaper to evolve, easily awakened, and had unique abilities that are on par with the SSR Units, if not better.
- For all SSR units, Captain Hawk come off as this. He's easier to max awakened than a regular SSR since he only requires 1 Cup to awaken despite having only 1 regular and debuff skill and his unique skill raises his stats by 50% (for a limited time event, it's normal value is 15%).
- Canon Foreigner: The Seven Disasters are characters original to the game.
- Chromatic Rock Paper Scissors: Most units have the attributes of Speed (blue), Health (green), and Strength (red). Speed beats Strength, Strength beats Health, and Health beats Speed. The game would later add the Light (yellow) and Dark (purple) attributes, which, when paired with the three base attributes, allow for more damage dealt against advantageous attributes with Light or disadvantageous attributes with Dark.
- Crossover: With the aforementioned Slime, Attack on Titan, The King of Fighters, Re:Zero and Stranger Things.
- Healing Boss:
- Various late game bosses can recover HP when their HP initially reaches zero, usually about 25-50%.
- Final Boss Ban can completely revive with full health if he is defeated while having certain amount of orbs (three for first phase, five for second phase) in his Ultimate Gauge. He can do this up to three times per phase.
- As most bosses have the same abilities as their playable unit counterparts, ones with heals naturally have access to these abilities, such as Lilia and Hendrickson.
- Manipulating the Opponent's Deck:
- Attack Disable, Buff Disable, Debuff Disable, Stance Disable, Recovery Disable, and Ultimate Move Disable cards prohibit opponents from using the respective card types for a set number of turns, limiting what can be done on their turn.
- Select bosses, such as Dahaaka, can remove cards from the player's deck upon successful attacks, regardless of the cards' ranks.
- Runic Magic: Rune Orbs are common pieces of equipment in the form of globes each inscribed with a mystic rune, and grant various effects depending on the type equipped.
- Tactical Rock–Paper–Scissors: While its card-based gameplay is similar to Fate/Grand Order, tactics-wise it was similar to Fire Emblem in any way. For example, a Strength unit (Red) is strong against HP Units (Green) but weak against Speed (Blue) Units.
