Fell Bullet Farming

At a Glance

Farm Mirror Dungeons by having Yi Sang's E.G.O Fell Bullet shoot down a low-level ally and use that momentum to clear enemies together. It is among the fastest farming methods, taking about 15 minutes per run when things go well. However, every floor is played on Hard, and you need low-level Identities as bullets plus a Starlight reserve, so learn Mirror Dungeons first. Unsuitable for deep-floor progression.

How It Works

• Fell Bullet is a Pride Pierce attack with 7 Attack Weight. The first Coin shoots the ally with the lowest HP; if it kills them, the second Coin hits all 6 enemies. If not, it only hits one random enemy.
• Before attacking, Yi Sang gains Torn Memory. At Threadspin Ⅳ with Pride Resonance, he gains twice the highest Resonance count (max 7). More Torn Memory raises damage to the ally and Critical damage, and he gains the same amount of Poise.
• At Threadspin Ⅳ, killing an ally returns 1 resource each of that ally's S1 and S2 affinities (the Corrosion version also returns S3). Bullets should have Wrath or Pride on S1 or S2.
• Bringing Tier Ⅲ Grand Welcome through Gift Observation gives +5 Pride at stage start and +2 Pride whenever an enemy dies.
• Tier Ⅲ Sharp Needle & Thread deals half the damage of the first skill to damage enemies each turn as extra fixed damage. With an AoE attack, each target takes half the total damage dealt to all targets, so groups fall together. Keep everyone except Yi Sang on Defense so Fell Bullet is the first attack.
• The Corrosion version of Fell Bullet does not distinguish allies from enemies and can shoot any number of allies. If several fall at once, you run out of bullets.

Preparation

• 
  User: Seven Assoc. South Section 6 Yi Sang. With 5–8 Speed, the fastest Yi Sang Identity, he fires before enemies act. LCB Sinner Yi Sang (4–8 Speed) or The House of Spiders: The Index Nursefather, a Poise Identity that crits easily, also work.
• Fell Bullet: Threadspin Ⅳ. At Ⅲ, killing an ally only returns the S1 resource.
• Early bullets (3): Low-level, Pierce-weak Identities. Around 75 HP reliably dies. Slow Identities with Wrath on Defense and on S1 or S2 work best.

  • 
    The best is the LCB Sinner Sinclair. She has 62 HP at Lv 1, and keeping her base E.G.O Branch of Knowledge equipped makes her Pride-weak too.
  • 
    Identities such as Dieci Assoc. South Section 4 Hong Lu, made Pride-weak with Repudiation, also work.
• 
  Late bullets (3–4): Pierce-weak Identities. Once your Gifts are complete, level does not matter. Placing Lobotomy E.G.O::Magic Bullet Outis on standby raises Fell Bullet damage at Pride Resonance 3.
• Resource gatherers: Used only in the first fight on floor 1. Bring a few Identities with Wrath or Pride on S1 or S2.
• Blessings: Star of the Beginning, Interstellar Travel, and Star-shower.
• Gift Observation: Tier Ⅲ Grand Welcome and Tier Ⅲ Sharp Needle & Thread.
• Starting Gift: Poise's Cigarette Holder. Add Stone Tomb if you have Starlight to spare.
• Packs: All floors on Hard: Flat-broke Gamblers → Hell's Chicken → Hatred and Despair → Line 2 → Line 1 or Line 4 - Section #3. Line 3 also works for floor 5. Avoid Line 5.

Starlight Balance

• Blessings and Gift Observations cost about 210.
• Starlight earned grows with Rest Bonus. If you rotate Sinners every run, the balance stays near zero even with Yi Sang and the 3 early bullets fixed.

Rotation

Floor 1

• Deploy 6 for the first fight: Yi Sang, one bullet, and 4 resource gatherers. Grand Welcome provides 5 Pride, so gather 2 Wrath and 1 Pride with the gatherers on turn 1 and fire Fell Bullet on turn 2. Keep Yi Sang on Defense on turn 1.

  • If you are unsure about resources, add an Identity with Wrath as a 7th.
• 
  If you have Faust's Hollow, you can open the first fight with it. Its first use in an Encounter costs only 2 Pride for the Corrosion version, so Grand Welcome's 5 Pride lets you fire it on turn 1. Each enemy death adds resources through Grand Welcome, gathering Fell Bullet's cost without spending bullets. Switch to Fell Bullet once you have 2 Wrath.

  • 
    Deploy Faust (such as the fast Heishou Pack - Mao Branch Adept) with one companion on Defense. Do not use an Identity that counterattacks as the companion.
• From the second fight to the floor 2 boss, advance with just Yi Sang and one bullet. Against bosses with few enemies, add one more bullet.
• At the shop, buy a Poise Gift and enhance it along with your Starting Gift. Enemy levels rise on floor 2, so they survive without Criticals. If you can one-shot the floor 2 fights otherwise, Bloody Gadget, Grey Coat, or Carmilla also work.

Choosing Rewards

• For battle rewards, take Cost or Starlight. When Wrath runs short, take resources of your scarcest affinity.
• For floor rewards, prioritize Tribulations that do not raise enemy HP. Buffs to enemy attacks or Clashes do not matter. Damage reduction also matters little, since boss fights shoot down many allies to boost damage.
• Enemy level increases also raise HP. On early floors the difference is small, so choosing by Gift tier is fine.

Floor 2

• Go to Hell's Chicken. Its events almost always give a Tier 3 Gift, and the boss is easy. Fell Bullet only hits 5 enemies in the boss fight, so add one more bullet.
• If a shop that allows enhancement appears, fuse Poise's Tier Ⅳ Clear Mirror, Calm Water and Tier Ⅳ Fragment of Conceit. Fragment of Conceit adds +8% Fell Bullet damage per resource spent.
• If you have room, also fuse Tier Ⅳ Fragment of Allurement and Tier Ⅳ Punctured Memory.

  • Fragment of Allurement: Fell Bullet inflicts Bleed on Critical hits, so its effect applies.
  • Punctured Memory: Raises base power and Coin Power of Pierce skills for positions 1 and 2, including E.G.O. Place Yi Sang in position 1 or 2.
• Also pick up Poise Gifts (Ornamental Horseshoe, Emerald Elytra, Nebulizer, Finifugality, and others) and Gifts that add resources.

Floor 3

• Go to Hatred and Despair. Otherwise, take S.E.A., which has only single-wave fights.
• At the shop, fuse the remaining Tier 4 Gifts. Before fights, restore Yi Sang's SP to 45. Low SP triggers the Corrosion version and uses up bullets early.
• Fight the boss (The Knight of Despair) with 10: Yi Sang and 6 bullets in front and 3 on standby, and defeat it within 2 turns. It gets rough once turn 3 begins.

  • With 4 or more on standby, the Knight can drop out of Fell Bullet's targets. If damage is short, use 12.
  • Use bullets with many Pride skills to keep Pride Resonance going.
• Sell Hatred and Despair's Value Disposal once your resources are sufficient. It restores SP when an ally has come off standby, which gets in the way of lowering SP on floor 5. Keep it if you plan to clear floor 5 with Line 3.

Floor 4

• Go to Line 2 with the same team as the Knight of Despair fight. The boss fight ends once you defeat the Sign of Roses.
• Your Gifts are complete by now, so you can usually skip the shop.

Floor 5

• Drop Yi Sang's SP to -45 and keep firing the Corrosion version of Fell Bullet.
• Line 4 - Section #3: The first fight ends with two Fell Bullets. Against the sheep boss, Overclock Fell Bullet on turn 1, then fire the Corrosion version from turn 2.
• Line 1: In the frog fight, Overclock Fell Bullet on turn 1. Shoot down only one ally, and keep Yi Sang's SP the lowest on the team. Breaking the frog's eye lowers SP and puts Yi Sang at -45. From there, advance with the Corrosion version.
• 
  Great Trichiliocosm Yi Sang makes it steadier. Advance with 8, and in fights where Yi Sang has 2 Skill Slots, fire Overclocked Fell Bullet and Great Trichiliocosm together. Damage holds up even when bullets fall, and you can drop SP to -45 even with Value Disposal. Fuse Tier Ⅳ Fragment of Hellfire beforehand.

Weaknesses and answers

• It is hard to build with few low-level Identities.
• You cannot use this until Hard is unlocked.
• Luck plays a big part. If you run out of bullets, Fell Bullet's second Coin only hits one enemy and the run falls apart. Manage SP so the Corrosion version does not hit too many allies.
• If you are short on low-level bullets, open the first fight of floor 1 with Hollow to save them.
• Unsuitable for deep-floor progression.

References

• Fell Bullet Team: The Complete Guide #1 (YouTube, in Japanese)