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This is a ranking page for the hero Fomortiis - Demon King from the game Fire Emblem Heroes (FEH). Read on to learn the best IVs (Individual Values), best builds (Inherit Skill), weapon refinement, stats at Lv 40, and more for Fomortiis.
| Heroes With the Same Name | |
|---|---|
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List of Contents
| Emblem Heroes - Eirika: Of the Sacred Featured Heroes | |||
|---|---|---|---|
Emblem Marth[9.0/10] |
Emblem Ike[9.0/10] |
Emblem Eirika[9.9/10] |
Mythic Lumera[9.0/10] |
Emblem Celica[9.0/10] |
Emblem Sigurd[9.9/10] |
Þjazi[9.0/10] |
Emblem Lyn[9.9/10] |
Brigid[9.0/10] |
Fomortiis[8.5/10] |
Mythic Gotoh[8.5/10] |
Legendary Guinivere[8.5/10] |

| Overall Rating | 8.5/10 |
|---|---|
| Reroll Ranking (excluding Inherit Skill) |
S (▶Reroll Ranking) |
| Ranking (including Inherit Skill) |
B (▶FEH Tier List) |
| Color / Weapon Type / Move Type | |
|---|---|
| Rarity | |
| What Kind of Character Are They? | ・Refined Ravager grants 【Fringe Bonus】, and 【Imbue】 to Fomortiis and allies within 2 spaces, slows down foe's Special charges and speeds up his own, grants bonus true damage and true damage reduction. ・Nightmare+ grants easier transformation, grants Fomortiis bonus true damage reduction and Special jumping, and inflicts Atk/Def penalties on foe. |
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Might: 14 Range: 1 Accelerates Special trigger (cooldown count-1). At start of combat, if unit's HP ≥ 25%, inflicts Special cooldown charge -1 per attack on foe and Atk/Def-6 on foe during combat (only highest value applied; does not stack), and also, if unit is transformed, grants Special cooldown charge +1 per attack to unit during combat (only highest value applied; does not stack). If unit's HP ≥ 25% at start of combat and foe initiates combat, reduces damage from foe's follow-up attack by 80% during combat. At start of turn, if unit is adjacent to only beast or dragon allies or if unit is not adjacent to any ally, unit transforms (otherwise, unit reverts). If unit transforms, grants Atk+2, and if foe initiates combat, unit can counterattack regardless of foe's range. |
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Cooldown Count = 3 Boosts damage dealt by 50% of unit’s Def. |
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If unit can transform, transformation effects gain "if unit is within 2 spaces of a beast or dragon ally, or if number of adjacent allies other than beast or dragon allies ≤ 2" as a trigger condition (in addition to existing conditions). If defending in Aether Raids, at the start of enemy turn 1, if conditions for transforming are met, unit transforms. Inflicts Atk/Def-10 on foe, neutralizes foe's bonuses to Atk/Def, reduces damage from foe's first attack by 30% ("first attack" normally means only the first strike; for effects that grant "unit attacks twice," it means the first and second strikes), reduces damage from foe's first attack by an additional 15 ("first attack" normally means only the first strike; for effects that grant "unit attacks twice," it means the first and second strikes), and grants Special cooldown count-2 to unit before foe's first attack during combat. If foe initiates combat, after combat, the closest foes within 4 spaces of target who have yet to act have their actions end immediately. |
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If unit initiates combat or is within 3 spaces of an ally, inflicts Atk/Def-4 on foe, deals damage = 20% of unit's Def (excluding area-of-effect Specials), reduces damage from foe's attacks by 20% of unit's Def (excluding area-of-effect Specials), unit makes a guaranteed follow-up attack, and reduces the percentage of foe's non-Special "reduce damage by X%" skills by 50% during combat (excluding area-of-effect Specials). |
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If a foe uses bow, dagger, magic, or staff and initiates combat against an ally with 2 spaces of unit, triggers【Savior】on unit. If unit triggers Savior, grants Atk/Def+4 during combat. 【Savior】 Unit takes ally’s space, enters combat in ally’s place, and receives all after-combat effects. Doesn't trigger if ally is on terrain that unit can't move to or if multiple units are able to use Savior during the same combat. If Savior triggers, after-combat movement effects don't occur. |
| Stat | Superboon/Superbane | IV Recommendation |
|---|---|---|
| HP (22) |
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★★★★☆ |
| Atk (14) |
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★★★★★ |
| Spd (5) |
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★☆☆☆☆ |
| Def (9) |
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★★★★★ |
| Res (9) |
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★★★★☆ |
◯ = Stat gains +4 with a superboon, ✕= Stat goes down by -4 with a superbane, - = No assets or flaws
| See the IV Checker for All Units | Trait Fruits—How to Change IVs |
When using an Ascendant Floret, we recommend getting the next superboon if it fits the hero. If not, consider what stat your hero needs most.
The best IVs for Fomortiis are +Atk and -Spd. Atk is a superboon and boosting it improves his combat performance, allowing him to potentially knock out his foes.
His Spd is a clear dump stat and he will be outsped by a large majority of the cast. Thus, it is the bane of choice.
We recommend +Atk when merging Fomortiis to +10 in order to improve his damage output. If optimizing for bulk, +Def is also a good choice.
| HOT | |
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This Near Save build aims to protect the team against melee threats through Savior. Shield Fighter provides the best defensive effects to ensure survival, where Fomortiis can use Nightmare+ to cripple the enemy team.
| HOT | |
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Fomortiis comes with a pretty good base kit for a Far Save role. Simply add an assist and a stat boosting Sacred Seal and he's good to go.
| Exclusive Weapon Effect from Refining (Special Effect Type) | |
|---|---|
| SP: 400 | |
| Might: 14 Range: 1 HP: 3 Accelerates Special trigger (cooldown count-1). Inflicts Atk/Def-6 on foe, inflicts Special cooldown charge -1 on foe per attack (only highest value applied; does not stack), and grants Special cooldown charge +1 to unit per attack during combat (only highest value applied; does not stack). Reduces damage from foe's follow-up attack by 80%, reduces damage from foe's follow-up attack by an additional 25, and reduces damage from foe's Specials by an additional 15 during combat (excluding area-of-effect Specials). At start of turn, if unit is adjacent to only beast or dragon allies or if unit is not adjacent to any ally, unit transforms (otherwise, unit reverts). If unit transforms, grants Atk+2, and unit can counterattack regardless of foe's range. At start of player phase or enemy phase, grants Atk/Def+6, 【Fringe Bonus】, and 【Imbue】 to unit and allies within 2 spaces of unit for 1 turn. Inflicts Atk/Def-11 on foe, and unit deals +25 damage during combat (excluding area-of-effect Specials). |
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Refined Ravager inflicts Atk/Def-17 on Fomortiis' foe, slows down their Special charges and speeds up his own.
In combat, refined Ravager grants Fomortiis +25 bonus true damage, 80% damage reduction on his foe's follow-up attack, +25 true damage reduction on his foe's follow-up attack, and +15 true damage reduction on foe's Specials.
At the start of each phase, refined Ravager grants Atk/Def+6, 【Fringe Bonus】, and 【Imbue】 to Fomortiis and allies within 2 spaces.
Refined Ravager heavily skews combat in Fomortiis' favor while giving him superb defensive effects. It even has good support by granting 【Fringe Bonus】, and 【Imbue】 to nearby allies, making it a great utility weapon in cases where Fomortiis cannot enter combat.
| Neutral Stats at Lv. 40 (5★) | ||
|---|---|---|
| 195 | ||
| HP |
46 |
Rank: 71/1341 |
| Atk |
44 |
Rank: 152/1341 |
| Spd |
15 |
Rank: 1167/1341 |
| Def |
46 |
Rank: 26/1341 |
| Res |
44 |
Rank: 42/1341 |
| HP | Atk | Spd | Def | Res | Total | |
|---|---|---|---|---|---|---|
| +10 Merges W/ Skill Bonuses | 51 | 63 | 19 | 51 | 48 | 232 | Lv.40 +10 | 51 | 49 | 19 | 51 | 48 | 218 |
| HP | Atk | Spd | Def | Res | Total | |
|---|---|---|---|---|---|---|
| +HP Lv.40 +10 | 53 | 48 | 19 | 50 | 48 | 218 |
| +Atk Lv.40 +10 | 50 | 52 | 19 | 50 | 48 | 219 |
| +Spd Lv.40 +10 | 50 | 48 | 23 | 50 | 48 | 219 |
| +Def Lv.40 +10 | 50 | 48 | 19 | 53 | 48 | 218 |
| +Res Lv.40 +10 | 50 | 48 | 19 | 50 | 51 | 218 |
| HP | Atk | Spd | Def | Res | Total | |
|---|---|---|---|---|---|---|
| 5★- Adjusted for Skills | 46 | 58 | 15 | 46 | 44 | 209 |
| 5★ Lv.40 | 46 | 44 | 15 | 46 | 44 | 195 |
| HP | Atk | Spd | Def | Res | Total | |
|---|---|---|---|---|---|---|
| 5★ Lv.1 | 22 | 28 | 5 | 9 | 9 | 73 |
| Hero |
HP |
Atk |
Spd |
Def |
Res |
Total |
|---|---|---|---|---|---|---|
| 53 | 50 | 16 | 50 | 43 | 212 | |
| 52 | 48 | 21 | 49 | 41 | 211 | |
| 50 | 49 | 17 | 48 | 43 | 207 | |
| 50 | 48 | 17 | 44 | 48 | 207 | |
| 49 | 47 | 16 | 49 | 46 | 207 | |
| 50 | 48 | 16 | 49 | 44 | 207 | |
| 49 | 49 | 17 | 49 | 43 | 207 | |
| 47 | 49 | 18 | 49 | 43 | 206 | |
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46 | 44 | 15 | 46 | 44 | 195 |
| 45 | 42 | 14 | 44 | 39 | 184 | |
| 47 | 37 | 23 | 37 | 30 | 174 |
Note: Stats bonuses from skills are not taken into account.
Fomortiis is a close physical attacker (range = 1). Therefore, when not accounting for the Weapon Triangle, the amount of damage he deals will be equivalent to his Atk minus the foe's Def stat.

Fomortiis comes with a new weapon refine for Ravager. When refined, it inflicts Atk/Def-17 on Fomortiis' foe, slows down their Special charges and speeds up his own.
In combat, refined Ravager grants Fomortiis +25 bonus true damage, 80% damage reduction on his foe's follow-up attack, +25 true damage reduction on his foe's follow-up attack, and +15 true damage reduction on foe's Specials.
At the start of each phase, refined Ravager grants Atk/Def+6, 【Fringe Bonus】, and 【Imbue】 to Fomortiis and allies within 2 spaces.
Refined Ravager heavily skews combat in Fomortiis' favor while giving him superb defensive effects. It even has good support by granting 【Fringe Bonus】, and 【Imbue】 to nearby allies, making it a great utility weapon in cases where Fomortiis cannot enter combat.
Fomortiis also has an exclusive remixed A skill in Nightmare+. This skill grants Fomortiis easier transformation conditions, inflicts Atk/Def-10 on his foe, neutralizes their Atk/Def bonuses, and grants Fomortiis 30% damage reduction on first attack, +15 true damage reduction on first attack, and a Special jumping effect before the foe's first attack.
More importantly, after combat, Nightmare+ ends the turn of the closest foes within 4 spaces of the foe who attacked him. This is an amazing effect which indirectly improves his survival by receiving less attacks, and the 4 space condition makes it a difficult skill to play around. Galeforce teams will require careful positioning in order to avoid this effect.
Fomortiis' status as an Armored Defense Mythic hero allows him to fulfill the Savior role without taking up a valuable non-Mythic hero slot in Aether Raids Defense team compositions. He can equip Savior skills and protect the team from powerful initiators, while the rest of his team can be fully geared towards offensive performance.
While Duma is another Armored Defense Mythic, his C slot is occupied by Upheaval+, which is the primary reason to field Duma. Fomortiis doesn't have an exclusive skill in his C slot, allowing him to equip Savior skills while fulfilling his non-Savior role.
His overall bulk is impressive, with base 46 HP, 46 Def, and 44 Res. His base 46 Def is quite high despite being an older hero, and his base 44 Res is also decently high. He will need these stats in order to fulfill his role, as he will not receive Mythic blessing bonuses due to being a Mythic hero himself.
Fomortiis takes 1.5x damage from armor-effective weapons like Slaying Hammer+, Randgríðr, or Thani, and one blow from this type of weapon will deal significant damage. Make sure you know what weapons you are up against before hopping too far into the line of battle!
Fomortiis takes 1.5x damage from beast-effective weapons like Brave Eliwood's Nini's Ice Lance or Picnic Flora's Sæhrímnir, and one blow from this type of weapon will deal significant damage. Make sure you know what weapons you are up against before hopping too far into the line of battle!
| Should You Unlock Potential for this Hero? | Cannot Unlock Potential |
|---|
Fomortiis - Demon King only appears as a 5 Star Hero. We will include whether or not you should Unlock Potential for Fomortiis - Demon King if a 4 Star version is released!
| Skill Name | Might | Range | Effect | Learned At |
|---|---|---|---|---|
| 4 | 1 | At start of turn, if unit is adjacent to only beast or dragon allies or if unit is not adjacent to any ally, unit transforms (otherwise, unit reverts). If unit transforms, grants Atk+2, and unit can counterattack regardless of foe's range. | 5★ | |
| 6 | 1 | At start of turn, if unit is adjacent to only beast or dragon allies or if unit is not adjacent to any ally, unit transforms (otherwise, unit reverts). If unit transforms, grants Atk+2, and unit can counterattack regardless of foe's range. | 5★ | |
| 9 | 1 | At start of turn, if unit is adjacent to only beast or dragon allies or if unit is not adjacent to any ally, unit transforms (otherwise, unit reverts). If unit transforms, grants Atk+2, and unit can counterattack regardless of foe's range. | 5★ | |
| 14 | 1 | Accelerates Special trigger (cooldown count-1). At start of combat, if unit's HP ≥ 25%, inflicts Special cooldown charge -1 per attack on foe and Atk/Def-6 on foe during combat (only highest value applied; does not stack), and also, if unit is transformed, grants Special cooldown charge +1 per attack to unit during combat (only highest value applied; does not stack). If unit's HP ≥ 25% at start of combat and foe initiates combat, reduces damage from foe's follow-up attack by 80% during combat. At start of turn, if unit is adjacent to only beast or dragon allies or if unit is not adjacent to any ally, unit transforms (otherwise, unit reverts). If unit transforms, grants Atk+2, and if foe initiates combat, unit can counterattack regardless of foe's range. | 5★ |
| This Hero has no Assist skills that can be learned. |
| Skill Name | Effect | Learned At |
|---|---|---|
| (Cooldown Count = 4) Boosts damage dealt by 50% of unit’s Def. | 5★ | |
| (Cooldown Count = 3) Boosts damage dealt by 50% of unit’s Def. | 5★ |
| Skill Name | Effect | Learned At |
|---|---|---|
| If foe initiates combat or foe's HP ≥ 75% at start of combat, inflicts Atk/Def-10 on foe during combat and reduces damage from foe's first attack during combat by 30%. If foe initiates combat, after combat, the closest foes within 4 spaces of target who have yet to act have their actions end immediately. | 5★ | |
| If unit can transform, transformation effects gain "if unit is within 2 spaces of a beast or dragon ally, or if number of adjacent allies other than beast or dragon allies ≤ 2" as a trigger condition (in addition to existing conditions). If defending in Aether Raids, at the start of enemy turn 1, if conditions for transforming are met, unit transforms. Inflicts Atk/Def-10 on foe, neutralizes foe's bonuses to Atk/Def, reduces damage from foe's first attack by 30% ("first attack" normally means only the first strike; for effects that grant "unit attacks twice," it means the first and second strikes), reduces damage from foe's first attack by an additional 15 ("first attack" normally means only the first strike; for effects that grant "unit attacks twice," it means the first and second strikes), and grants Special cooldown count-2 to unit before foe's first attack during combat. If foe initiates combat, after combat, the closest foes within 4 spaces of target who have yet to act have their actions end immediately. |
5★ | |
| If unit's HP = 100%, removes the condition to transform. At start of combat, if unit's HP = 100%, unit makes a guaranteed follow-up attack during combat. | 5★ | |
| If unit's HP ≥ 50%, removes the condition to transform. At start of combat, if unit's HP ≥ 50%, unit makes a guaranteed follow-up attack during combat. | 5★ | |
| Removes the condition to transform. Unit makes a guaranteed follow-up attack during combat. | 5★ | |
| If unit’s HP = 100% and unit initiates combat, unit makes a guaranteed follow-up attack. Grants Special cooldown charge +1 per attack. (Does not stack. ) | 5★ | |
| If unit’s HP ≥ 50% and unit initiates combat, unit makes a guaranteed follow-up attack. Grants Special cooldown charge +1 per attack. (Does not stack. ) | 5★ | |
| If unit initiates combat, unit makes a guaranteed follow-up attack. Grants Special cooldown charge +1 per attack. (Does not stack. ) | 5★ | |
| If unit initiates combat or is within 3 spaces of an ally, inflicts Atk/Def-4 on foe, deals damage = 20% of unit's Def (excluding area-of-effect Specials), reduces damage from foe's attacks by 20% of unit's Def (excluding area-of-effect Specials), unit makes a guaranteed follow-up attack, and reduces the percentage of foe's non-Special "reduce damage by X%" skills by 50% during combat (excluding area-of-effect Specials). | 5★ | |
| If a foe uses bow, dagger, magic, or staff and initiates combat against an ally adjacent to unit, triggers【Savior】on unit. If unit triggers Savior, grants Atk/Def+1 during combat. 【Savior】 Unit takes ally’s space, enters combat in ally’s place, and receives all after-combat effects. Doesn't trigger if ally is on terrain that unit can't move to or if multiple units are able to use Savior during the same combat. If Savior triggers, after-combat movement effects don't occur. |
5★ | |
| If a foe uses bow, dagger, magic, or staff and initiates combat against an ally with 2 spaces of unit, triggers【Savior】on unit. If unit triggers Savior, grants Atk/Def+2 during combat. 【Savior】 Unit takes ally’s space, enters combat in ally’s place, and receives all after-combat effects. Doesn't trigger if ally is on terrain that unit can't move to or if multiple units are able to use Savior during the same combat. If Savior triggers, after-combat movement effects don't occur. |
5★ | |
| If a foe uses bow, dagger, magic, or staff and initiates combat against an ally with 2 spaces of unit, triggers【Savior】on unit. If unit triggers Savior, grants Atk/Def+4 during combat. 【Savior】 Unit takes ally’s space, enters combat in ally’s place, and receives all after-combat effects. Doesn't trigger if ally is on terrain that unit can't move to or if multiple units are able to use Savior during the same combat. If Savior triggers, after-combat movement effects don't occur. |
5★ |

| Value of Skills | ★★★☆☆ |
|---|
Fomortiis has Beast Follow-Up 3 and A/D Far Save 3 as inheritance options.
Beast Follow-Up 3 is the skill of choice to inherit when using Fomortiis as fodder. However, we recommend you keep at least one copy in your barracks, as he is a powerful hero.
| List of Source Heroes | The Best Fodder Units |
If you have feedback about this hero page, let us know in the comments section below!
Fomortiis is a limited time Hero who can be pulled from a Mythic Hero Summoning event. They do not appear in regular summons.
Note: Not currently a featured hero in any Summon events.
| Voice Actor (English) |
Mark P. Whitten |
|---|---|
| Illustrator | Daisuke Izuka |
| Appears In |
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| Heroes from Emblem Heroes - Eirika: Of the Sacred | |||
|---|---|---|---|
Emblem Marth[9.0/10] |
Emblem Ike[9.0/10] |
Emblem Eirika[9.9/10] |
Mythic Lumera[9.0/10] |
Emblem Celica[9.0/10] |
Emblem Sigurd[9.9/10] |
Þjazi[9.0/10] |
Emblem Lyn[9.9/10] |
Brigid[9.0/10] |
Fomortiis[8.5/10] |
Mythic Gotoh[8.5/10] |
Legendary Guinivere[8.5/10] |
▶︎Return to the Colorless Heroes Page
| Close-Range | Ranged |
|---|---|
Colorless Breath |
Colorless Dagger |
Colorless Beast |
Colorless Bow |
Colorless Tome |
Staff |
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