Arguably the strongest, and possibly coolest, boss in Dark Souls 3, Slave Knight Gael has put down countless Ashen Ones. If his kill count against all players globally was recorded, it would easily be in the millions. Across 3 different phases, Gael unleashes standard, strike, thrust, and dark damage as well as being able to encourage the heavens to rain down blue-white bolts that deal lightning damage.
The Slave Knight's origins are unknown, as he is mentioned in Dark Souls 3 to be a wanderer who likely ended up in The Ringed City much like how the player did and is experiencing the converging of worlds and times in a similar manner. He met the Painting Woman, creator of the Painted World, at some point and sought to find her a pigment to complete her work. This is when the player finds him; after he was finally able to track down a source for the required color: the Dark Soul. Though, the blood of the pygmy lords had dried up long ago, so Gael consumed the soul of darkness in order to turn his own blood into the black pigment needed.
Wielding his greatsword while performing fast maneuvers both toward and away from the player, he is a tough foe to defend against or find an opening to land a strike on. Patience is a virtue here, so be sure to conserve enough stamina to roll away or through all of his many, frenzied assaults. Depending on the player's weapon and build, there will be different tactics that one should focus on, such as whether to roll or block as well as contemplating weapon damage type choice.
Updated on September 28, 2021, by Reyadh Rahaman:Besides the epic battle with Slave Knight Gael, there is a lot more about him than players realize. In typical FromSoftware fashion, Gael's design, boss arena, fighting style, and much more hint at some of the deepest lore in the franchise.
Due to one's confrontation with Gael being very action-packed, there isn't any time for players to absorb all the interesting details. Thankfully, however, due to the collective accounts of gamers worldwide, a broad picture has been painted for many to enjoy this fascinating slice of the DS3 universe.
Melee Strategy #1: Use A Strike Weapon
One of Gael's 3 main weaknesses in DS3 is strike-type damage. Most hammers and great hammers possess this damage type as well as a few ultra greatswords. These are also quite capable of staggering Gael, albeit far more easily in his first phase.
All throughout this fight, if one is using a heavy weapon such as these that consumes a lot of stamina per attack, be sure to only hit the boss after he finishes one of his moves. Missed blows born from carelessness will leave the Ashen One open to one of Slave Knight Gael's many slams, stabs, and other assaults.
Melee Strategy #2: Use A Frost Weapon
Frost weapons are all-around awesome against almost any adversary, be it in PvP or PvE. Gael has a crucial weakness to this status ailment in DS3, which can be exploited by the player. All 6 of the weapons with innate frostbite potential can be used effectively here, however, some are better than others to use against this 3-phase boss.
Since Vordt's Great Hammer also deals strike damage, players can use it to devastate Gael's health bar with each swing, especially in his phase 1 form. As always, just be sure to only launch attacks when there's a clear opening.
Melee Strategy #3: Use The Hollowslayer Greatsword
During phase 2 and phase 3 of the fight, Gael will be a hollow-type enemy, meaning that he will take additional damage from certain weapons, such as the Hollowslayer Greatsword. This greatsword deals 20% bonus damage, which is immensely helpful against the Slave Knight's huge health bar.
The moveset of the Hollowslayer Greatsword has a thrusting maneuver with the two-handed strong attack that maximizes the range of the blade so that players can hit Gael from a safer distance when needed. Be sure to also two-hand it in order to take advantage of the hyper armor frames, and, as always, gauge one's stamina accordingly.
Spellcaster Strategy: Use Poison & Toxic Spells
Some more of Gael's weaknesses in DS3 are poison and toxic, which can both be activated simultaneously for massive damager-per-second devastation to the boss's health bar. The best spells to inflict such maladies, Poison Mist and Toxic Mist, are pyromancies that require 10 and 15 Faith respectively, making them both great weapons for pyromancer and miracle builds.
For sorcerer builds, players will be interested in using the Storyteller's Staff, as its weapon skill unleashed a cloud of purple haze that acts very similarly to Poison Mist in appearance and effect. This would also allow the player to use sorceries more fluidly in conjunction for a more diverse offense.
It is also worth noting that those seeking to use this dastardly tactic can also use consumables to aid in afflicting Slave Knight Gael with ailments. Poison Knives can be greatly helpful to keep adding to the status bar's progress, though, there is an even more disrespectful way to fight the knight. Dung pies, which apply the toxic status to both the target and the player, can be used to great effect if one is running low on FP. Just be sure to bring some Blooming Purple Moss Clumps in order to avoid succumbing to the same ailment that one is trying to inflict. Unfortunately for Slave Knight Gael, he has no such option and will soon fall to the player's devious tactics.
Slave Knight Gael Lore
Lore From The Slave Knight Set
As players normally need to do to get a better idea of a character's story, taking a look at specific item descriptions can help piece together Gael's past and motivations. Firstly, by looking at the armor Gael wears as an NPC (the Slave Knight set), players can glean a tragic backstory. Armor of this kind was only used by slave knights, who were literally used as fodder in "the bleakest of battles".
These slave knights were thrown at enemies until their skin was charred and their bone twisted to the point where most went mad, though, were still never relieved of their duty. No one knows where slave knights originated, as Gael is the only one gamers can meet in the franchise, however, this may mean that all others have perished except Gael himself.
Lore From The Executioner's Greatsword
This unique greatsword that deals strike damage is Gael's primary weapon in his NPC form. Despite not possessing any cutting power based on in-game mechanics, it is mentioned to have been used specifically for decapitation, which is odd since execution weapons often possess a sharp blade to more easily cut through flesh and bone. However, in its description, it is mentioned to belong to a "debauched executioner", though does not refer to Gael directly.
Gael could very well be this "debauched executioner", however, remember that this sword is only used by NPC Gael, who has not yet been corrupted by either time or from feasting on pygmies, meaning that the item description could be implying that Gael somehow got this greatsword from a possibly hollow executioner before beginning his travels, or even found it, like how the player can find it in a graveyard in The Ringed City.
Lore From Gael's Greatsword
This greatsword is in fact a different, much older, version of the Executioner's Greatsword. Its item description mentions that Gael carried this weapon "from beginning to end", possibly confirming that Gael was once an executioner and the blade's original owner. However, "beginning" can have many meanings and may refer to the start of Gael's pilgrimage to find the blood of the Dark Soul.
Dark Souls 3 is available on PlayStation 4, Xbox One, and Microsoft Windows.