1 Meter: HP double > light Reckoning > HP double > light Reckoning > LP double > Shadow Reckoning > Devil's Divide + Sadistic Drop Ender (51%)
2 Meter: HP double > light Reckoning > HP double > light Reckoning > LP double > Shadow Reckoning > Shadow Devil's Divide Ender (58%)
( Damage calculation notes)
Notes: Gargos's counter breaker damage is relatively weak. If he counter breaks with no white life already on the opponent, he struggles to build a level 4 ender without spending meter, so his 0-meter combo is quite low. Fortunately, this isn't too common, so you'll usually get to level 4 in real matches. His best two uses of meter in a combo, by far, are Shadow Reckoning, which does good damage for a shadow linker, and Shadow Devil's Divide ender, which will always finish a combo strong. If you are freestyling a combo and you have to choose between these two uses of meter, the shadow ender does slightly more damage on average, but make sure you're at level 4 first.
Gargos does not fight alone. For the cost of one shadow meter, Gargos can summon a minion to help him fight his opponent by inputting +KK. These minions will move around the stage on their own and automatically attack if the opponent gets within their personal space. They can help Gargos on offense by controlling space and keeping the opponent preoccupied, and also help him on defense by interrupting the opponent's combo. In general, they are built to be a nuisance to the opponent while Gargos gets to act freely.
There are two minion types, and Gargos can have one of each type on screen at once. Summon Izzik, a pitchfork wielder, by inputting the regular shadow move command. He slowly walks back and forth in place, stabbing the space in front of him if the opponent gets near. He can also stab upwards as an anti-air attack, if the opponent jumps at the wrong time or Gargos juggles the opponent into Izzik's range. Summon Dretch, a little fat dude, by holding any P or K during the shadow move's screen freeze. He scampers around along the ground and attacks with a (non-overhead) jump at the opponent's head. All of the minion's attacks are classified as projectiles, so they can be dodged by projectile invincible moves, or blocked like normal. The minion attacks cannot cross up; always block away from Gargos, even if the minions end up behind you.
In order to get rid of the minions, you must attack them directly. Izzik has two hit points, while Dretch has three. Hitting the minion with any attack will knock the minion over, putting him out of commission for a few seconds, which gives you a chance to go attack Gargos uninhibited. While Gargos is being hit, all minions that have been knocked over will stay knocked down, letting you get your full punishment without being interrupted. When the combo is over, or after the few seconds have passed, the minion will then get back up and continue where he left off if he has hit points remaining. Like ARIA's assist types, you cannot hit the minion more than once at a time, even with fast-hitting shadow moves; the minion will always fall to the ground after being hit with any strike. You can, however, hit both minions with the same attack if they are both in range. High-damage attacks do not kill the minions quicker, so feel free to poke them with fast light attacks where possible, so Gargos has a more difficult time protecting his friends.
Gargos can also control the minions to a small degree. Using the +K command, Gargos can tell all his active minions where on screen he wants them to be. They can either be in Cover Mode (+LK), which means they will idle around close to Gargos, or they can be in Creep Mode (+MK), which means they will try to walk around close to the opponent instead. Minions automatically summon in Creep Mode and will walk towards the opponent after appearing. If you want them in Cover Mode from the very start, you can optionally hold back during the shadow freeze to keep them close to you. While this adds an extra wrinkle of control for expert Gargos players, when you are first picking him up, it's recommended to just keep all minions in the default Creep Mode and let them harass the opponent.
After 10 seconds of being active, the minion will have purple smoke above their head; this indicates that the minion has access to his Special Attack. Gargos can use the Kill Command (+HK) to get all his active minions to use their Special Attack. Izzik will perform a multi-hitting spin attack with his pitchfork, keeping a blocking opponent locked in place briefly, while Dretch will fly off the top of the screen and belly flop the opponent's head a few moments later, and this attack is an overhead. It is easy to forget about the Special Attacks with all of Gargos's other abilities, but if you manage to keep your minions alive for over 10 seconds, don't forget to pick a spot when your opponent is frustrated and activate them! Gargos get a second or two to go in and perform jumping MP overheads or Devil's Divide command grabs while the minions lock him down.
If all this wasn't enough, Gargos can also pick up his minions using Devil's Divide! If you press up or forward while holding him, Gargos will throw the minion in two different arcs toward the opponent, acting as a projectile. When they land, they will begin harassing the opponent like normal. Gargos can also press back to eat the minion, which gives him instinct meter, or press down to very nicely set the minion back on his feet, as shadow lords do. Pressing P or K while holding the minion will pummel him and immediately activate his Special Attack, so you don't have to wait the normal 10 seconds.
Got all that? It's a lot of words to describe a fairly simple concept; summon a minion, then let him do his thing while you zone or rush down with Gargos. They are a very strong use of shadow meter and Gargos should be trying to summon minions as often as he can. Summoning minions has some startup time, so you'll need to score a knockdown before you can safely do it; guaranteed safe options include Gargos's regular throw, his sweep, his Oblivion launcher ender, and his Sadistic Hurl hard knockdown ender. Against some characters who struggle with mobility or don't have shadow meter, you may also be able to use the highly damaging Sadistic Drop to safely summon minions. When they are active, your opponent will be trying his best to punch the minions whenever he has a moment of respite, so try to keep him preoccupied with Oblivion from long range, or normals and command grabs from close range so he cannot freely hit them. When you are starting out, you don't need to worry too much about changing the minion's modes (apart from using the Kill Command if you see they are glowing purple), or picking them up with Devil's Divide. It is fine to just summon the minion wherever possible and then continue to play your normal Gargos game, and force your opponent to be smart defensively to get rid of them.
Gargos has two main openers, one for close range and one while far away. Oblivion, also known as "Portal Punch", is his ranged opener, although only the light version beneath their feet will start a traditional grounded combo. All versions of Oblivion, including the shadow version, are quite unsafe on block, solidifying their use as a ranged attack only. None of the versions are overheads or lows, even though the attack angles appear above or below the opponent. To continue ranged combos, Gargos uses his combo trait, similar to Glacius, which makes use of ranged auto-doubles and ranged Oblivion linkers.
Light Oblivion is the fastest of the three non-shadow versions; it is not entirely dissimilar in use to Kan-Ra's Spike attack, as it is most useful for catching people who flinch while they are trying to moving forward, perhaps as they are pestered by a minion. To avoid light Oblivion, one good option is to walk forward and block pre-emptively, as the attack does negligible chip damage. Really, you shouldn't feel bad blocking several of these attacks in succession, even if a minion is also up in your grill. You'll build some meter and come out not too worse for wear while you plan an appropriate counter attack, and Gargos has no way to mix you up from long range. Your other primary option is to jump over the attack. Gargos will suffer a lot of recovery if the attack misses, perfect for landing a hit on a minion or Gargos himself if you are in range. If nothing else, just jump forward without attacking, and you can close the gap between you and Gargos.
Medium Oblivion punches directly in front of the opponent. It always knocks down and starts up a bit slower than the light version, but is more useful for trying to keep opponents in place. The heavy version starts up the slowest of all, and always ground bounces the opponent. Because it attacks from above the opponent, they cannot easily jump over this attack, making it something worth throwing in from time to time if the opponent insists on trying to jump towards you while you are zoning them. It can also start (or extend) juggle combos due to its ground bounce property. Shadow Oblivion starts up lightning fast, making it a useful long-range punish tool. If it hits on the ground it will also open a normal combo! But because it does very little damage on hit, this should be used fairly situationally as a long-range punish or reaction move, and should be avoided if other moves will do the same job.
If you are not zoning with Oblivion, Reckoning is your best close range combo starter. Reckoning looks a lot like M. Bison's Psycho Crusher from the Street Fighter series, and Gargos has both ground and air variants. If your opponent blocks Reckoning, Gargos will bounce away into the air and will be granted one additional air action, which can be used to attack with a normal attack or air Reckoning, or perform one additional jump. You'll be limited to just one extra air action until you land, though; if you choose to do Reckoning again and your opponent blocks, you'll be forced to land. Some (perhaps many!) characters will be able to punish Gargos as he bounces away from Reckoning before he can act. Try this out in training mode with your favorite character to find the counters; for example, Gargos himself can use medium Reckoning as a punish from most ranges.
Light Reckoning is the fairly standard forward-traveling special move that all KI characters have. On hit, it will cause stagger, making manuals fairly straightforward, but you can also go directly into auto-doubles or linkers if you choose. Light Reckoning will only combo off medium and heavy normals, though, which means if you want to start a combo off a light attack, you must use light Oblivion, which will be unsafe if blocked. Medium Reckoning fires Gargos into the air at a 45-degree angle, and is a superb anti-air; use this often to catch people jumping over your Oblivion zoning, or people who think it's okay to hang out in Gargos's air space.
Heavy Reckoning sends Gargos through a vertical portal and lands on top of the opponent. This move is invincible on startup, but it is horribly slow as well as unsafe on block. While it can be used a reversal (and instinct canceled if you have instinct available), I recommend not using this move too often. You'll struggle to hit anything, and offensive opponents will always be able to block or get out of the way of it, then punish you. Gargos can also do Reckoning in the air, with very similar applications to ARIA's Crescendo move. Explore this move to find creative ways to jump over attacks and punish from long range. Despite his size, Gargos in the air is especially mobile with quadruple jumps and air Reckoning.
Even though that list is long, don't panic; Gargos tends to keep most of his combo starters within the traditional combo system. If you manage to dunk someone with heavy Oblivion as they are jumping around, you can keep the combo going by juggling with light Oblivions. If they eventually get bounced close enough to Gargos, he can snatch them out of the air with heavy Devil's Divide for added measure, but all these attacks are combo breakable. If you are near the corner, Gargos's command grab, Devil's Divide, becomes scarier as the forward throw followup, Sadistic Hurl, leads to a combo via an easy manual. And, of course, if you have the presence of mind to capitalize in time, any time a minion hits your opponent, you will be able to keep the combo up.
Gargos's Oblivion linker can be used either at close range or far range, as per his combo trait. The linker version of this special always appears directly over the opponent's head and hits 1, 2, or 3 times; this is how you can differentiate it from Gargos's ranged auto-doubles, which appear in front of the opponent at different angles depending on the strength. At close range, you should tend to use Reckoning as a linker, however, because it does more damage.
Gargos has a myriad of enders, but some of them are quite situational and in practice it's not as complicated as it seems. From long range, your only option is to use Oblivion, the only ender that will reach, and it will ground bounce the opponent. If you have some KV remaining, you can sprinkle in some light Oblivions as juggles to get some extra damage, or you can just use the time to summon a minion if you prefer to not risk being broken. Near the corner, Gargos has Reckoning as his wall splat ender, which lets him land Devil's Divide for unbreakable damage (and additional meter stealing), or the standard post-wall splat mixups.
Devil's Divide, when used as an ender, will punch the opponent a predetermined number of times depending on the ender level, and then perform one of four different actions, depending on the direction you are holding the analog stick. The ender versions are quite similar to the options you are given if you land Devil's Divide in neutral; holding up (or no direction) gives you the damage ender, holding back gives you the battery ender, and holding down gives you the advantage ender. The only difference is holding forward will not cause the opponent to land on his feet after being hurled, but will instead give Gargos a hard knockdown. Gargos can use this time to set up space, even summoning both of his minions if he wants. Because it forks into four different options, you will use Devil's Divide ender quite often. Like most characters, choosing to default to the damage or battery options if you are unsure what to do will work just fine.
Well, that would be the case if not for Gargos's final ability in instinct. Pressing all three punches performs Eruption, a 0-damage attack which causes Gargos to explode the stone skin off his body, ending his instinct prematurely and leaving him with half his remaining instinct gauge. Eruption is basically a Guilty Gear burst. The attack is invincible (but wildly unsafe if blocked), and Gargos can use Eruption while he is being comboed and knocked down, unlike any other move in the game. If your opponent knocks you down and uses heavy normals on your wakeup, your only option is to use Eruption to stop it. Alternatively, you can try to combo break and if you lock out, immediately use Eruption to save yourself. Eruption causes a soft knockdown on hit; from close range, if you try to summon a minion, your opponent will be able to quick rise and punish you.
Because this instinct is so unique, it means it is best used in unique situations. Unlike most other instincts in the game, activating it does not make for the world's best reversal, because a smart opponent will be attacking Gargos on his wakeup with heavy attacks. Gargos can activate instinct, and if his opponent has not pressed a heavy button, Gargos can simply absorb the attack and begin a combo. However, if he sees that his opponent did press a heavy normal, then he must immediately use Eruption. Most of the time, the end result of this exchange is that Gargos spends half his instinct meter to do 0 damage and get a knockdown and some breathing space. While this is a very expensive cost, Gargos's weak defense means that sometimes, and if we're being honest probably quite often, you will have to do it if the fight isn't going your way.
Because it is a generally poor reversal option against smart players, Gargos should try to activate instinct at a distance, where his opponent cannot immediately hit him with a heavy normal. It will greatly strengthen his zoning and mid-range game, because traditional ways to approach Gargos when he has minions on the screen are to use horizontal-traveling special moves, and armor has no trouble absorbing those. If you are fighting a Gargos who has activated instinct at long range, just try to stay calm and block his assault of Oblivions and minion attacks. Because he cannot dash up and grab you, his mixup threat is greatly diminished, and you will likely have a very difficult time trying to hit him. Take some pot shots at some minions if you can while you wait for the instinct to drain.
Because Gargos has some air superiority in him, you'll need to get to know his air normals as well. Gargos flaps his wings when you press jumping HK, pushing Gargos back and causing a huge hitbox in front of him. This move is great at creating space between you and your opponent, and some characters will have a difficult time contesting this attack, or chasing Gargos down after he has used it. Jumping HP causes Gargos to swoop downward, then upward. It's unsafe if it gets blocked and should be used sparingly except in flashy combos. Jumping MK is a useful cross-up attack.
Jumping MP stops all of Gargos's upward momentum and causes him to land immediately again. This can be used as an instant overhead, and because it happens so fast, opponents stand a good chance at getting hit by it. It has two big disadvantages, though; it is one of the very rare jumping attacks that is not an opener, so it cannot start combos unless a minion gets involved, and it is very unsafe on block, punishable even by heavy attacks after Gargos lands. You might escape punishment against some beginner and intermediate players, but good players will punish you for trying to use jumping MP in close quarters too often. However, if a minion is near an opponent, jumping MP becomes an especially strong option, as fighting through the minions to punish is usually too difficult, and it gives Gargos a strong high-low mixup game.
Gargos's other up-close option is the Devil's Divide command grab. With no grounded overhead and no advantage-on-block special move, Gargos's main way to threaten you from close is with Devil's Divide. The light version is the fastest, while the medium version causes him to hop forward a bit first (useful when canceling off a normal for a tick setup), and the heavy version acts as anti-air. After you grab them, you can optionally hit any punch or kick to pummel your opponent up to three times before you choose one of four enders by pressing a direction; Devil's Divide acts like a Smash Bros throw. The pummels are combo breakable, but they are often worth tacking on because they increase the damage rather substantially. Three heavy knees to the gut will add on around 12% to your throw's damage, and while you can identify the strength of the strikes based on how Gargos hits you, it happens quickly and is difficult during a match to break on reaction.
The four Devil's Divide finishers are pretty straightforward. Holding up or no direction causes Gargos to suplex you through a portal for extra damage. Holding back makes Gargos steal some shadow meter from his opponent. Holding forward throws the opponent a short distance away onto their feet, leading to a combo in the corner. And lastly, holding down sets the opponent onto their feet right in front of Gargos, where he has +4 frame advantage for a mixup. As with the ender version of Devil's Divide, there's nothing wrong with defaulting to the damage or meter stealing options more often than the others. They are good all-purpose options that you can just use without thinking in case you get overwhelmed. Using the forward throw option to start a combo is good, but only if you are in the corner; you can safely ignore this option otherwise. And the ender that gives Gargos frame advantage is great for cheeky resets, but since this option does no damage by itself, you'll need to make your reset count.
Ultimately, though, Gargos really has one primary goal in mind; he wants to get meter so he can summon minions. Minions are the glue that makes all of Gargos's gameplan come together. They enhance his zoning, frustrate his opponent's attempts to approach, strengthen his rushdown, and will sometimes save Gargos on defense as well. If you choose to spend most of your meter on other uses, or you can't keep your minions alive for very long, I think you will probably feel somewhat lost with Gargos.
When you don't have meter to summon, you'll need to bide your time until you do. Take advantage of Gargos's well above average zoning by making good use of Oblivion from full screen. Throw out the light one to trap them from moving forward on the ground easily, but jumping forward will beat this strategy. Just like Glacius, Gargos needs to be extra aware that his opponents will want to jump forward at him to close the gap, and always have medium Reckoning primed for anti-air in addition to occasionally sprinkling in heavy Oblivions just to discourage jumps. If you miss an anti-air and have to block a jump-in, Gargos will struggle mightily with no fast invincible attack and a large hitbox open for abuse. Try your best to not let this happen by playing solid and being ready for "obvious" jumps when you can tell that your opponent is fed up with blocking Oblivions.
At close range, Gargos isn't dead by any stretch, but you will have to play riskier to get anything done. You will have to mix it up between jumping around and using air Reckoning or his unique air normals (like jumping HK) to create space, his few good grounded normals (crouching MP and standing MK in particular) sometimes canceled into ground Reckoning, or taking a bet and doing Devil's Divide. While Devil's Divide is a good option in Gargos's toolkit and should be represented fairly often, just be warned that a failed command grab has worse implications for Gargos due to his poor defense, and he isn't particularly great at stopping opponents from jumping away from the grab without resorting to a massive callout with heavy Devil's Divide. If you do land a grab and you don't have at least one meter, use Sadistic Appetite to steal some meter so you can feed your minion addiction. It's worth more than the damage in this instance.
Once you have meter, find a safe opportunity and bring a minion out. Gargos always gets to summon safely after throws, many Devil's Divide finishers (using Sadistic Hurl as a combo ender will even let him summon two minions if he chooses, while others such as Sadistic Drop are situationally useful depending on your opponent's character and shadow meter), after Oblivion ender from full screen, or after canceling light Oblivion on block during your zoning. Whether you prefer Izzik or Dretch is largely up to personal preference; I would experiment with both and see which one you prefer helping you fight solo. Izzik attacks more often and covers more space, but he takes fewer hits before he dies. Dretch can take an extra hit, but he often has a mind of his own and won't cover you when you expect him to.
Feel free to continue your basic gameplan and let the minions assist you in whatever ways they deem fit, or really dig into training mode to find specific setups and combos that use the minions to smother your opponent. Try to keep them alive as long as you can, but don't worry if they die; that's their job, and remember that your opponent will often have to take extra risks to hit the minions. Over the long term, you will end up capitalizing on some of the mistakes your opponent will make just because the minion exists on the playing field. And Gargos is just fine with that. He didn't come to play fair.