Johnny is a recurring playable since the first release of Guilty Gear X.
Johnny is a very awkward character to the untrained player; he cannot run, and his normals have a lot of lag, but decent priority and range to make for good, yet decisive pokes. However, a thing about him is his Mist Finer, which appears to be a more offensive version of May's Mist Finer (from the first Guilty Gear game) in the form of the traditional 3-way delayable special, in that it can be delayed while each button used at the end of the motion determines whether it aims up, mid, or low, thus creating mindgames (said delaying can be canceled to even create feints). The slashes can even negate projectiles with good timing, but sees not much practicality. Also, Johnny can walk around while delaying Mist Finer, and in later installments, he can even phase dash, giving him some interesting options during most situations.
Johnny can throw coins at his foes via his Glitter Is Gold move, and he begins each round with eight coins. While a very impressive move in its own right for possible zoning and pressure set ups like for all projectiles in terms of competitive usage, coins are also used to power up Johnny's Mist Finers. The effects of Mist Finers vary with coin level; with level 2 increasing combo possibilities and damage, and level three being a multi-hit combo in its own right of multiple Mist Finers in succession. These moves were key to Johnny's famous "Mist Loops", possible in most versions of the game, though different loops are used in different games. In earlier installments, his level 2 low and mid Finers "popped" the opponent up, allowing for a devastating follow-up. His Bacchus Sigh can be used during corner traps and wakeup, as it despite being a slow-moving cloud that does no damage, it makes his Mist Finer unblockable while it latches onto the target, enabling Johnny many devastating combo setups. Overall, Johnny is a character that requires execution and hefty setups, but once such setups are placed, Johnny can be very hard to stop in the hands of a good player, especially if one has a thing for utilizing a gratuitous amount of mindgames.
The speed issue can be circumvented through a technique known as "Mist-Canceling," by attacking with any move which can be special canceled, going into Mist Stance, and quickly canceling the stance (this is a technique usually used for mindgames from a defensive position but also for offense on a riskier level, as well as spamming it for meter gain, but in a more combo-oriented game like Guilty Gear, this benefits Johnny greatly). This circumvents the recovery animations of many of Johnny's attacks, and enables him to apply pressure more effectively, though his attacks must connect in order to be canceled in this manner. In Guilty Gear X, his Mist Cancels were incredibly fast, enabling him to execute some of the highest damage Tension-less combos in the entire game; they have since been considerably nerfed, but are still a crucial part of Johnny's gameplay on both combos and defensive mindgames.
Johnny's Ensenga (Swallow Drill Fang) in the XX games can be TK'd (Tiger Knee'd; motioned with an up-forward/up-back command at the end to jump just before the attack executes via the button press), serving as a situational overhead, and his primary aerial combo finisher. The attack hits twice, with the first hit being untechable. Many of Johnny's more advanced options revolve around corner traps involving these "one-hit" Ensengas.
In past installments, Johnny's Divine Blade was his staple air combo move, with "Jump-Installed" Divine Blade Combos being some of Johnny's fiercest options. However, as of Accent Core, Divine Blade has been nerfed and comes with an alternate version known as Killer Joker as his primary tool for extended aerial combos; like Divine Blade, it can be FRC'd, and it also restores Johnny's jump/AD. His single overdrive, What is my Name?, does solid damage, and despite it being close range-oriented, it is useful for escaping tough spots due to its invincibility frames and high/upper hitbox.
In Slash, Johnny's new Jack Hound move made him quite dangerous, in that it is a quick distance-closing slash that can pass through the foe and causes stagger, making it great for interrupting several of his foe's strategies. Not only that, Johnny can clash with attacks as well as phase through a majority of them via its invincibility (this even includes projectiles) to bypass foes to set up for powerful punishes. The can even be done during his Mist Finer delay stance with faster startup, giving him even more mindgame potential. What's more, Jack Hound can even be Roman Cancelled, making it hard to punish on block, or even for a quick meaty combo.
In Accent Core, his Mist Finer effects have been changed. Level 2 Mid now causes ground slide, and Level 2 Low launches the foe backwards; both still open up options for Johnny, with Mid being crucial to his AC corner traps, and Low allowing for an air combo. The damage dealt, both by the Finers and their follow-ups is lessened, however, and his earlier Finers are generally preferred by Johnny players. In Accent Core, Johnny's Bacchus Sigh suffered greatly, as it is now among the game's slowest moves, making his old mist-traps much more difficult to execute. His throw, though simple, is perhaps the game's best, as it guarantees an air combo/coin. Also in Accent Core, Jack Hound may have been nerfed by making it a Force Break (and thus, making it cost meter). However, Jack Hound has gained a nice buff, the Jack Hound Return: an Overdrive attack followup that not only does extra damage, but enables Johnny's Mist Finer to level up per time that Jack Hound Return connects, and thus, giving Johnny a second option should his coins run out or better yet, a way to level up Mist Finer even faster when used in tandem with his coins.
The latest version of Guilty Gear XX, Accent Core Plus R, has given Johnny a number of incredible buffs. He is now regarded as one of the game's stronger characters. For starters, his original crouching from the first GGX returns as his 3H, which has plenty of active frames to use as a meaty wake-up tool; this also ties into his buffed Bacchus Sigh - crucial to his deadly corner unblockable traps, which has been restored to its Slash speed, and once again makes his corner traps lethal. His Mist Finers have had their untechable time increased, give him his Upper Mist Finer loop back, and opening up/easing the execution of a great number of combos. He once again has reliable one-hit Ensenga combos from midscreen on most of the cast, and improved proration on a number of moves have buffed his damage output. Buffs to both the speed of his Mist Cancels and his dash speed have strengthened his maneuverability and ability to pressure (as well as tension-less combo possibilities). Glitter Is Gold has no doubt improved on its zoning, for he gains a new command for it (214H) that makes him toss it up in a more upward arc via his throw animation, enabling anti-air control. He has also gained a different version of his EX form's second Overdrive, Unchou no Iai (Cloud Peak's Re-sheath; the latest patch gives it more range to hit with), but compared to his other buffs it is somewhat inconsequential.