Cú Chulainn (Prototype)

This is a beginner-friendly guide to Cú Chulainn (Prototype) in Fate/Grand Order (English). It breaks down what makes Cú Chulainn (Prototype) strong, his basic stats, skills, and Noble Phantasm, plus the Ascension and skill-up materials you'll need to raise them.

Cú Chulainn (Prototype)'s Basic Information

Name	Cú Chulainn (Prototype)
Class	★3 Lancer
Obtain	Saint Quartz Summon Friend Point Summon

Cú Chulainn (Prototype)'s Strengths

High-Damage Attacker with Special Attack Against Wild Beasts

In addition to having a strengthened Noble Phantasm, Cu Chulainn [Prototype] can grant himself a high-magnitude Special Attack [Wild Beast] effect with his skill. He also gains a Quick Performance Up effect from his NP, allowing him to deal high damage against Wild Beasts even with a neutral class advantage.

Excellent NP Effects

His Noble Phantasm has an Ignore Defense effect, making it effective against enemies with high defense buffs. Additionally, it includes a Defense Down effect that increases with Overcharge, which can boost the damage of follow-up attacks or a second Noble Phantasm.

Includes a Low-Probability Instant Death Effect

The Noble Phantasm also has an Instant Death effect that scales with Overcharge. However, the success rate is relatively low compared to other Instant Death NPs, and since he does not have an Instant Death Success Rate Up skill, it is difficult to rely on him for Instant Death purposes.

High Durability with Excellent Evasion

His second skill grants him an excellent Evasion (3 hits) that has no turn limit and remains until he is attacked 3 times. Since it is not removed by the passage of turns, it is easy for him to survive even against enemies with high attack power.

Tenacious Even if Evasion is Broken

He gains a Defense Up buff at the same time as the evasion, allowing him to reduce damage taken even if the evasion is bypassed. Especially when used against Archers, he can fight tenaciously for a long time.

Also Deals High Damage with Critical Hits

He possesses a high-magnitude Critical Strength Up and Star Absorption effect, letting him deal significant damage with critical hits if stars are supplied. However, he has no means of generating stars himself, so it is necessary to provide them through support.

Strong Against Debuff Effects

He has a Debuff Resistance Up (3T) skill and possesses Magic Resistance as a class skill, making him less susceptible to debuffs. However, since it doesn't guarantee a successful resist even at Skill Lv 10, it shouldn't be over-relied on.

Servants with Good Synergy

Compatible Supporters
	Scáthach-Skadi (★5) She provides a high-multiplier Quick buff and up to a 50% NP charge, supporting both damage output and NP spamming.
	Summer Scáthach-Skadi (★5) In addition to a high-multiplier Quick buff, her 50% NP charge makes it easier to fire NPs repeatedly. Her Buster buff and Buster Critical Strength buff also raise the damage of Buster attacks, and her Star support makes critical hits easier to land.
	Altria Caster (★5) She can support the team with a 50% NP charge and an ATK buff. In high-difficulty content, her NP's Anti-Purge Defense provides vital protection for the whole party.
	Merlin (★5) He provides AoE Invincibility and HP recovery to bolster the party's survivability. He is also an excellent offensive supporter, offering Critical Star generation from his NP and Critical Strength buffs from his skills.
	Zhuge Liang (Lord El-Melloi II) (★5) He provides up to a 50% NP charge along with an AoE ATK buff. He also possesses an NP charge reduction and AoE defensive buffs, making him an excellent choice for defensive utility.
	Jeanne d'Arc (★5) Her NP grants HP recovery and AoE Invincibility. As a Ruler, she is rarely defeated, making her a great choice for defense-oriented stall teams.
	Brynhild (★5) She can apply Critical Strength and Star Concentration buffs, making critical hits much easier to land. Her NP can also increase the Critical Star drop rate, making her a specialized critical supporter.
	Mash Kyrielight (★3-★4) She has Target Focus (Taunt), DEF buffs, and Invincibility on her skills, plus additional DEF buffs on her NP, allowing her to protect allies effectively in high-difficulty content.
	Hans Christian Andersen (★2) He provides turn-based Critical Star and NP generation via his skills. His NP grants HP recovery and, by chance, ATK/DEF buffs, supporting both party survival and damage output.

Cú Chulainn (Prototype)'s Skills & Noble Phantasm

Skills & Noble Phantasm

Class	★3 Lancer
Cards
Obtain	Saint Quartz Summon Friend Point Summon
HP / ATK	10098 / 7082（Lv Max）
Skill 1	Rune Spell B【CT：7~5】 Increase own Critical Strength by 18-45% (3T)[Lv] Increase own Debuff Resist (3T)[Lv]
Skill 2	Protection from Arrows B【CT：7~5】 Apply Evade to yourself (3 times) Increase own DEF by 8-16% (3T)[Lv]
Skill 3 (Enhanced)	Beast-Slayer B++【CT：7~5】 Apply Special Attack [Wild Beast] 50-100% to yourself (3T) [Lv] Increase C. Star Gather Rate (3T) [Lv]
Noble Phantasm (Enhanced)	「Gáe Bolg」 Increase own Quick Card effectiveness (1 turn) Deal massive damage that ignores DEF to a single enemy[Lv] Decrease their DEF by 10~30% (3 turns)[OC] Medium chance to inflict Death[OC]
VA	Kazuya Nakai
Illustrator	Nakahara

Append Skill

Extra Attack Boost	Increase Extra Attack Card's effectiveness by 30~50% for yourself
Load Magical Energy	Begin battle with NP charged at 10~20% for yourself
Anti-Caster (ATK Up)	Increase own ATK against Caster class by 20-30%

Card Performance

Alignment & Traits / Class Skills

Alignment & Traits
Alignment	Lawful / Balanced / Heaven
Traits	Male / Divine
Class Skill
Magic Resistance C	Increase Debuff Resist
Divinity B	Apply Damage Plus 170 for yourself

Recommended Skill Leveling by Priority

Skill 1	Priority: ★★☆ You can boost the multipliers of Critical Strength up and debuff resist up. It boosts critical damage, so prioritize leveling it after Skill 3.
Skill 2	Priority: ★☆☆ You can boost the DEF Up multiplier. It works even unleveled, but the skill cooldown reduction from leveling makes reusing the DEF Up or Evade (3 hits) easier. If you use it in clears, level it up.
Skill 3	Priority: ★★★ You can boost the multipliers of the special attack and star concentration up. Since it boosts special-attack damage, level it first.

Ascension & Skill Enhancement Materials

Ascension Materials

Stage 1	Lancer Piecex4
Stage 2	Lancer Piecex8 Void's Dustx10
Stage 3	Lancer Monumentx4 Seed of Yggdrasilx8 Claw of Chaosx2
Final Ascension	Lancer Monumentx8 Claw of Chaosx4 Octuplet Crystalsx8
Total	x12x12 x6x10x8x8 1,330,000 QP

Skill Enhancement Materials

Lv1	Gem of Lancerx4
Lv2	Gem of Lancerx8
Lv3	Magic Gem of Lancerx4
Lv4	Magic Gem of Lancerx8 Seed of Yggdrasilx4
Lv5	Secret Gem of Lancerx4 Seed of Yggdrasilx8
Lv6	Secret Gem of Lancerx8 Void's Dustx7
Lv7	Void's Dustx13 Proof of Herox12
Lv8	Proof of Herox36 Octuplet Crystalsx16
Lv9	Crystallized Lorex1
Total	x12x12x12x1 x12x20x48x16 13,600,000 QP

Append Skill Enhancement Materials

Lv1	Gem of Lancerx4
Lv2	Gem of Lancerx8
Lv3	Magic Gem of Lancerx4
Lv4	Magic Gem of Lancerx8 Black Beast Greasex2
Lv5	Secret Gem of Lancerx4 Black Beast Greasex4
Lv6	Secret Gem of Lancerx8 Primordial Lanugox2
Lv7	Primordial Lanugox4 Cursed Beast Gallstonex2
Lv8	Cursed Beast Gallstonex5 Reactor Core of Dawnx10
Lv9	Crystallized Lorex1
Total	x12x12x12x1 x6x6x7x10 13,600,000 QP

Illustrator / Voice Actor & Final Ascension Art

Illustrator / Voice Actor

Parameters

Ascension Art (Final Ascension Spoiler Warning)

We have included images up to Final Ascension. Because they contain spoilers, please proceed with caution.

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1st Ascension

2nd-3rd Ascension

Final Ascension

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