Diarmuid Ua Duibhne (Saber)

“Well then, let me show you. My death-bringing lance, er, sword!”

Móralltach and Beagalltach, Fury and Passion, the two swords gifted by the god Manannan; these are the weapons carried by Diarmuid’s Saber form. A version which emphasizes the knight’s relation to the gods of Celtic mythology, Diarmuid (Saber) is an ST Quick damage dealer whose kit strikes a fine balance between dependable offense and formidable defense.

Diarmuid (Saber)’s primary source of damage is his NP Móralltach. While the NP itself is an unexceptional single-target Noble Phantasm for the most part (its defense buff removal, unfortunately, happens after damage), its high hit count results in considerable NP refund when infused with external Quick buffs and his third skill Beagalltach, which also amps up the already-decent NP gain of Diarmuid’s normal command cards. The critical reliability provided by The Knights of Fianna's Honor and Diarmuid’s own Star gain capabilities also contribute to his NP Gain potential and damage. Lastly, Diarmuid is also solid defensively thanks to Beagalltach’s Defense Up and Evasion from Mana Burst (Jump), the latter of which also acts as his primary damage boost.

Diarmuid’s potential, however, is limited by his own questionable damage ceiling. Having only a single damage increasing skill with slightly subpar modifiers and a one-turn duration, he excels at neither burst nor sustained damage. Coupled with Diarmuid’s lack of a personal NP Charge, these factors make him reliant on external support and CE choice to perform well in a team environment, as he needs external aid in terms of NP Charge and Critical Damage buffs, among other things.

In summary, Diarmuid is a Servant whose issues limit what he can ultimately accomplish, yet there are definitely situations in which he can shine. His high survivability and good command cards make him a good fit for soloing, and with proper support he becomes a reliable single-target Quick damage dealer option, especially against Lancers.

High NP Hit Count

Móralltach’s high hit count means that it pairs well with external Quick buffs, allowing the NP to generate a lot of critical stars as well as a decent amount of NP charge. Combined with his normal cards and potential criticals, Diarmuid is capable of refunding a majority of his NP charge under the right setup, making the NP relatively spammable.

Good NP Gain and Reliable Criticals

Diarmuid (Saber)’s NP gain comes primarily from the combination of decent base generation stats, the NP Gain Up from his third skill, and his criticals, which Diarmuid can perform quite reliably. This critical consistency comes from the fact that his high hit count translates into decent star generation (particularly on his Quick and Extra cards), which is further complemented by The Knights of Fianna's Honor’s instant critical stars and Star Absorption Up.

Good Survivability

Having a three-turn Defense Up buff from his third skill and an Evasion on his first, Diarmuid is a rather survivable damage dealer. While the latter being tied to his primary damage buff makes it hard to capitalize upon, it is generally still a welcome reduction of incoming damage and can be a deciding factor in a pinch.

Unimpressive Damage

While Diarmuid comes with a solid Attack stat as well as a single-target NP, his one damage boost only lasts for one turn. While his critical hits are reliable, he has no way to increase their damage outside of the turn in which his first skill is active. As his NP gain-related advantages rely on using his Quick and Arts cards, his overall damage potential is somewhat reduced, while his Buster cards (being mostly unbuffed) aren’t particularly impressive either in terms of damage.

Reliance on External Aid

Diarmuid’s qualities of high NP hit count, good NP gain and reliable criticals only truly shine when he is given sufficient buffs. Without them, his damage-related problems will become apparent, while his NP gain won’t be sufficient to perform NP spam on a reliable level.

Situational Utility

Diarmuid’s NP has a built-in defensive buff removal, but unfortunately, the effect is only applied after its damage, meaning that an enemy with Evasion will still be able to defend against his NP damage. His NP’s Instant Kill is also situational at best due to its low chance.

Being a Servant who relies more on his natural capabilities, Diarmuid (Saber) does not require high skill levels to function. Still, if he is to be used as a primary Saber, all three of his skills contribute to his offense in one way or another, and should be invested into, even if not maxed.

• Mana Burst (Jump) A acts as Diarmuid’s primary and only damage boost, and scales well with additional levels, the effectiveness of its buffs being doubled at max level compared to level 1. Naturally, its Evasion aspect doesn’t scale with level, but it benefits from the cooldown reductions at levels 6 and 10. This skill should be the first of Diarmuid’s skills to be leveled. 
• While the Star Absorption Up of The Knights of Fianna's Honor B is pretty central to Diarmuid’s performance, its value is sufficient even at base level. Still, the amount of stars this skill provides increases with every additional level. It is definitely recommended to level it a bit (e.g. level 4) as early as possible, but it otherwise has less priority than Diarmuid’s other two skills.
• Beagalltach B+ is a pretty solid skill overall, as both its effects (Defense Up and NP Gain Up) are universally useful. While its indirect offensive benefit makes it lose out in priority compared to Mana Burst (Jump), it is definitely a solid second.

Starting NP Gauge CEs are generally prime choices for Diarmuid (Saber), as well as hybrid versions thereof. Secondary effects featuring Quick Performance Up, NP Damage Up, Attack Up and Critical Damage Up are preferred. In general, pure damage-increase CEs are not as recommended but may still be used, especially those with the aforementioned offensive effects.

• Kaleidoscope / The Imaginary Element / Dragon’s Meridian: Diarmuid’s NP is an important part of his kit thanks to the damage, stars and refund it provides. These CEs allow him to access it very early in a stage, and can alleviate early pressure away from the team while potentially allowing him to have it ready again by the third wave.
• Holy Night Supper / One Summer / Golden Sumo: Boulder Tournament / Knights of Marines / Distant Pilgrimage / Summertime Mistress: Hybrid CEs which offer Starting NP as well as long-term benefits, this category of CEs is less suitable for early burst but allows Diarmuid to get his NP ready before the final wave without much effort.
• The Black Grail: Within a well-supported team, the Black Grail’s damage potential is a very alluring prospect for someone like Diarmuid, and can be used against bosses with high HP pool.
• Imaginary Around / Midsummer Moment / Dangerous Beast / Projection / Dumplings Over Flowers / Holy Night Sign: These CEs offer less raw damage compared to the Black Grail but also improve upon Diarmuid’s other offensive aspects, resulting in more balanced performance.