Editing Dark Mode

{{nihongo|'''Dark Mode'''|Dモード|D Mōdo|lit. "D Mode"}} is a special form [[Riku]] can enter in ''{{c|Kingdom Hearts|game}}'' and ''[[Kingdom Hearts Chain of Memories]]''. Riku initially receives the ability to enter Dark Mode from [[Maleficent]], and he uses it against [[Sora]] after he reclaims the [[Keyblade]]. Riku loses it after his body is taken by [[Ansem, Seeker of Darkness|Ansem]].

[[Vanitas]], one of the main antagonists of ''[[Kingdom Hearts Birth by Sleep]]'', as well as the [[Vanitas Remnant]], wears a bodysuit similar to the one Riku wears while in Dark Mode. Under [[Ventus-Vanitas|Vanitas's possession]], [[Ventus]] also wears this suit.

In ''Kingdom Hearts Chain of Memories'' and ''[[Kingdom Hearts Re:Chain of Memories]]'', since Riku is a playable character, he has a specific moveset while in Dark Mode. Dark Mode is only triggered when the player manages to fill up the Dark Points gauge up to 30 by either breaking cards or taking damage and while having any card(s) in use at that time. If Riku takes a Card Break, he loses DP and cannot enter Dark Mode, even if the gauge was at 30. Once Riku enters Dark Mode, his cards get automatically reloaded (adding 1 reload if an Enemy Card is in use), and the [[Potion]] and [[Hi-Potion]] cards that he eventually had in his deck depending on the World he's in are removed until the next reload after he reverts to normal. Once in this form, he can stay in that state for as long as he has Dark Points remaining. He loses a certain amount of Dark Points if his card is broken, with the number of Dark Points lost equal to the difference between the enemy's card and the broken card. For example, if an enemy breaks Riku's 2 card with a 9 card, Riku loses 7 DP. Riku also loses DP when taking damage, in ''Kingdom Hearts Chain of Memories'', the amount of DP he loses is proportional to the damage taken, while in ''Kingdom Hearts Re:Chain of Memories'', Riku loses 5 DP from each hit taken, regardless of damage, making attacks or situations that deal continuous damage deplete a lot of points and end the form very quickly. When his Dark Points reach zero, Riku reverts to his normal form. Dark Mode is permanent during the fight against [[Game:Zexion|Zexion]] where Riku starts immediatly in Dark Mode and never loses any DP.  

While in Dark Mode, Riku's main combos have increased speed, he can utilize additional Sleights, and his Soul Eater reacts to the darkness, increasing in power. His three-hit combo has the power to stun with the second hit, flames bursting from the Soul Eater upon the combo finisher. Riku possesses an aerial spin-slash (counting as a combo finish), also able to [[Double Jump]] behind an enemy and perform a downward slash with the next attack, and his [[High-Speed Step]] becomes a dash that covers more distance; however, it grants no invincibility. While under the possession of Ansem, Riku has access to almost all of his dark powers, including a few new abilities such as one that shoots a razor-thin disc forward.

During the first battle with Riku's Dark Mode in ''Kingdom Hearts'', he uses supreme agility to jump far distances, either away from or towards Sora's location. While Sora is in close range, Riku will attempt a powerful spin-slash. He can also perform a single slash before following it up with a rushing slash, and he is also able to deal immense damage. Magic has no effect on Riku, so the player must rely solely on the Keyblade. Jars can be found on the sides of the battlefield which contain HP Orbs and Hi-Potions.

When tackling a possessed Riku, who wields Dark Mode to its maximum potential via Ansem, one must take extreme caution. Riku will dodge almost every hit, attacking with just as much speed. Guard and retaliate immediately afterwards. Depending on what attack is blocked, a certain number of Tech Points may be earned. As his HP dwindles, Riku will begin to empower himself further with Darkhand state, gaining new abilities and adding additional properties to his old abilities. His dash attack fires Shock Slashes that can be blocked back to him, and he can use Helm Split to perform a jump attack that fires bursts of darkness from the ground and ends Darkhand state. Eventually, he will also gain the ability to use Dark Aura, and when he reaches his final HP bar, he will stay in Darkhand state permanently. Again, magic has no effect, the Keyblade and its abilities the player's only chance of survival.

When fighting the Riku Replica in ''Kingdom Hearts Chain of Memories'', he attacks in a fashion comprised of a two-hit combo that stuns on the second hit. He also uses a jump-attack that causes flames to burst from the Soul Eater. Over the series of four battles, the Riku Replica gains access to Sleights, each very powerful and threatening to the player's HP Bar.