There are a total of 29 achievements in Etrian Odyssey III:

• (6 total) for reaching each of the Strata divided across 25 floors.
  
• (2 total) relating to guild functions.
  • 1 for letting 3 adventurers rest.
    
  • 1 for retiring 3 adventurers.
• 2 related to Land Exploration
  
• 2 related to Sea Exploration
  
• 1 for Forging a weapon
  
• 1 for earning 250,000 Ental.
  
• (2 total) relating to Combat
  • 1 for defeating a boss in a single turn.
    
  • 1 for dealing 1,000 damage in a single hit.
• 4 for defeating post-game bosses
  
• 3 for defeating route-specific bosses
  
• 1 for defeating the 6th Stratum boss
  • and 1 more for defeating it on Expert difficulty

• 1 for unlocking the Shogun class.
  
• 1 for unlocking the Yggdroid class.
  
• 1 hunting all Pasaran variants
  
• 1 for completing everything else (100%)

The following sections are rough instructions on navigating the floors. For in-depth floor Boss/FOE/enemy details, I suggest using a full walkthrough or referring to the wiki.

I put this near the top of the guide so that you can plan ahead and reduce backtracking related to side quests. Going forward (M) indicates a mission (M-D = Deep City; M-A = Armoroad) and (S) relates to the sea quests/activities. The following quests are not listed under a Stratum floor:

• Man Versus Nature - Have a Farmer in your current party (lv8+ = better reward).
  
• Letter in a Bottle I - Talk to the innkeeper. Before giving him advice, talk to someone else to add another option. This will triple your potential reward.
  
• Tanniyn Hunting (S) - Find a Giant Fish icon and attempt to fish it multiple times.
  
• Lost treasure - 5 steps:
  1. Head to B1F and talk to the guard (LT) at point D2. Ask about Ruffalo.
     
  2. Talk to the innkeeper.
     
  3. Go to the Butterfly Bistro → Gather information → Long-haired blond man
     
  4. Talk to the innkeeper and select the The blond man.
     
  5. Return to the Butterfly Bistro → Gather information → Long-haired blond man
• Filling the Monstrous Codex - Talk to the members of the Senatus to start the quest.
  
• Filling the Item Compendium - 130 items in the compendium. Talk to the members of the Senatus twice—once to start the quest and once more to confirm that you have 130 entries.

NOTE: If you don't see a particular quest, it's most likely locked behind floor/story progression or an item unlock. An example of this would be Tanniyn Hunting which becomes available after acquiring Ned's Harpoon.

Waterfall Wood
Reached the First Stratum.

• Prelude to the Forest (M) - Fully map the accessible areas of the floor including the middle area with 2 treasure chests. Automap works just fine for this task.
  
• Butterfly Bistro's New Menu - Slimy Leg/Frog Cheek = Forest Frog
  
• The Fisherman's Rest - Head to A2 (REST) during the day.
  
• Too Close to Home - 3 Greedy Lizards will spawn upon entering the floor. Defeat all of them.
  
• Mooning over clover - Find the 4-leaf (CLOVER) at D3. Do not take it for twice the reward.
  
• The bird pair - The birds in question (PAIR) are in the treasure room at point D3.

• Ho! The Gigapede! - Gigapede Leg = Gigapede
  
• Request from the Firm - Small Flower = TAKE point (1st Stratum)

• The Bond Between Guildmates - 4 steps:
  1. Head to B2F.
     
  2. Return to the Butterfly Bistro → Gather information → Bertram Guild Member
     
  3. Head to the campsite (B1) on B2F point D6.
     
  4. Make your way to the campsite on B3F.
     • Trigger 2 events (B2 & B3) at points D3 & F4.

• Proof of Will (M) - Defeat the Stratum Boss—Narmer at point B6.
  • To reach Narmer, herd it into a corner and use the side passages.
• Amber Delight - Head to the dead end at A4 (AD) and then select: Smoke the nest, Climb the tree, and Cut the nest off the branch
  
• The Fish Festival - Defeat a minimum of 15 fish (Fanged Fish or Devilfish) without leaving (50+ for the maximum reward). The quest concludes in town after an announcement.
  
• Dragon Quests (1/3) - Head to the Moon Door to at point E4 to meet a guard. Then, head to the Armoroad Inn to get an item that will let you hunt. (DRAGON) at B4F point E1.

Undersea Grotto
Reached the Second Stratum.


To get full access to the Second Stratum:

• Meet (OLYMPIA) at B6F point A4.
  
• Trigger an event at A5 (same floor) and defeat the FOEs that spawn.
  
• Return to Olympia and then report to the Senatus.
  
• Make your way to B8F, triggering an event with a guard along the way.
  
• On floor B8F, enter the crevice at point A1 and defeat the Abyssal Death (AD). Receive the Sea Bead after the battle.
  
• Head to the campsite on B7F (REP) and report your progress to Kujara then the Senatus.
  
• Head to B6F point B3 (BEAD) and then place the Sea Bead to disable the torrents.

• Messages from aeons past I - Search the North walls of point C2 to obtain (FOSSIL).
  
• Shrouded in the Abyss - (ANEMONE) can be fought at point E1. This area can be reached by unlocking and passing through the Moon Door found on B6F (point D7).

• Danger in the Undersea Grotto (M) - See Stratum notes above.
  
• Clinic's Request - Thick Throat = Koolasuchus
  • Condition: Kill with Volt damage.
• Statue of Salvation - Search the dead end at point C3 (SOS) and leave the offering.

• Professor Scott's all-nighter - Inspect the North wall (SAN) at point D5 and keep observing until you trigger 3 consecutive battles.
  
• Deep blue - Indigo Pith - CHOP point (Highest rate at B7F point B2 at 70%)

• Door to the Deep City (M) - Defeat (KETOS) at point A6 and enter the (DEEP CITY).
  • Don't forget to pick up the (STAR KEY) along the way.
    True Ending/Eldest Path Note To qualify for this ending:

    • Promise Olympia not to reveal the location of the Deep City
      
    • Break that promise and tell Flowdia of the Deep City's location.
• Unknown Mutation - Inspect the dead end (GB) at point B2 and defeat the Glutton Beast that will spawn and ambush you.

Molten Caves
Reached the Third Stratum.

• Wishing on a branch - Break the (BRANCH) at point E4.
  
• The gourmand's demands - 4 steps:
  • Head to point E3 to spawn a Pomona Taker (PT).
    
  • Chase and defeat the Pomona Taker.
    
  • Search the wall behind it for a Pomona Fruit (PF)
    
  • Defeat the 3 newly spawned Pomona Takers behind you for maximum reward.
• Letter in a bottle II - 5 steps:
  • Talk to both of the innkeepers at Armoroad and Deep City.
    
  • Obtain Scarlet Sage = TAKE point (3rd Stratum)
    
  • Talk to Missy at the Butterfly Bistro and pick Yes.
    
  • Deliver the Scarlet Sage to the Deep City innkeeper.
    
  • Deliver the Green Remedy to the Armoroad innkeeper.
• Ant Agony - The 2-way connector (AA) becomes available after accepting the quest. The Ant Queen (AQ) can be found at the end of this linear area. Please note that killing this boss while it's asleep can drop an Execution Jaw, therefore giving you access to a strong Dagger—the Danda-chakra.
  
• Elval's hobby - The quest will officially start once you enter the 3rd Stratum through B9F. The fastest way to end this is to defeat 2 Mud Lurker foes on B9F for a quick 30 points. Otherwise, you can keep battling on higher floors (up to B12F) for more points. Scoring 250 points will get you the maximum reward.

Otherworldly visitors (M) - Win the battle at point C4 (EO) and select Wait.
• After turning in the quest, talk to Seyfried and make your way to B11F. Kujara will stop you. Talk to both city representatives and then you'll be able to pick a side.
  True Ending/Eldest Path Note It doesn't matter which side you pick.
• Messages from aeons past II
  • Stegosaur Fin = Stegosaurus
    
  • Red Tusk = Cave Elephant
    
  • Dino Calcaneus = Fire Lizard (B11F)
• Searching for springs - Find all 3 spots at A1, A7, and D1 (S1-3) for the maximum reward.

• The sculptor's request - 3x Igneous Rocks = Lava Beast
  • Condition: Kill with Ice damage.
• Dragon Quests (2/3) - (WYRM) will appear at point C6 after you inspect and pull out the sealing rocks (SEAL) located at points C1, 4A, and D7.

• Protect the Gatekeeper (M-D)
  
• Slay the Gatekeeper (M-A) - Regardless of the route, you'll fight the (GATEKEEPER) at D4.
  
• The jeweler's request - Turn in any (3rd Stratum) mining resource to finish the quest. The item you turn in will dictate your reward. Missy will automatically pick the highest tier item so if you want one of the lesser rewards, sell the other items:
  • Corundum: Panic Guard
    
  • Clastic Rock: Gale Amulet
    
  • Pyrargyrite: Critical Belt

Abyssal Shrine
Reached the Fourth Stratum.

• The gates close if you pass through in the same direction as the arrows are pointing.
  
• After passing gate (G1) on B15F, gate (G2) will lock. To proceed, flip the switch (GS) on B16F.

• The shrub fruit - The fruit can be found at D6 (SHRUB).
  
• Elval's Grim Truth - 2 steps:
  • Press the (SWITCH) at point A5.
    
  • Head to point B5 to find (KRAKEN).

• Statues of limitation - At point A4 (SOL), press all the buttons once (except for the x). If you mess up, just use the x to reset the puzzle.
  
• Treasures of the depths - The reward will depend on which item you turn in:
  • Candlestick = B14F A2 (Strength Belt)
    
  • Stylish Jar = Buy from the shop (Death Magatama)
• A comrade sleeping below - Upon entering the floor, a FOE (SLEEP) will spawn. Chase and force it into the pit at point E6. Instead of following it down the hole, head down the stairs at E5 to finally corner and defeat it.
  
• Elval's hobby II - Similar to Elval's hobby I but much easier. Gather 45 times at any of the 4th Stratum points for the maximum reward.

• Decipher the Shrine's mysteries (M-D)
  
• Search for Amarantos (M-A) - Both the Amarantos and the location to use the Ibn Ghazi Powder can be found in the same location at point A4 (AMAR).
  • After finding the mission goal, instead of immediately returning to town you can continue to explore closer to the exit. I strongly suggest unlocking the 2-way connectors near the exit to save time for your subsequent visit with the next mission.
• An artisan's choice
  • 5x Spearhead Chips = Deep Marine
    
  • 1x Damascus Edge = Deep Raider (B15-16F)
    • Condition: Kill with Strike damage.
• Secrets on a pedestal - An event will trigger against the wall at point E4 (SOP):
  • Sky Tablet = Top
    
  • Earth Tablet = Left
    
  • Man Tablet = Right

• Locate the teleporter (M) - The mission goal is the same for both routes at point F3 (KIRIN). The route you chose determines the boss you fight. Armoroad = Kirin; Deep City = Shin.
  True Ending/Eldest Path Note After turning in this mission, DO NOT accept the next mission if going for the True Ending. CTRL+F Progenitor for further steps.

Porcelain Forest
Reached the Fifth Stratum.

• The Torii Gates will only activate if you pass through it from the front. The maps below show depict the front as the "foot" of the Torii Gate icons.

• Praying with pampas grass - Pampas (GRASS) can be found at point C6.
  
• Monster from across the sea - Talk to the Armoroad innkeeper and find (ALRAUNE) at D6.
  • Requires the completion of the Letter in a bottle quest line.

• A salty exploration - The (SALT) is at C5 within the blackout zone.
  
• A secret request - 2 steps:
  • Enter B18F to receive a Mushroom Dagger. Equip it.
    
  • Finish off the enemy at point F7 (MS) using the Mushroom Dagger.
• Dragon Quests (3/3) - To fight (DRAKE), head to point B2 and during the event, select No. Afterward, head to the Armoroad Inn and then return to the same spot at B18F (B2).

• Rock of wages - Taking the Warm Stone (WS) at D1 will trigger some battles and give you twice the reward.
  
• Sisters - 7 steps:
  1. Talk to the Armoroad shopkeeper.
     
  2. Visit the branch store in Deep City during both the day and night.
     
  3. Tell the truth.
     
  4. Talk to everyone at the Armoroad Inn, Iver Port, the Guild, and Missy at the Bar
     • Gather Information:
       • Tomboy hammerist Nerona
         
       • Astrologist Aura
  5. Return to the branch store and pick Winter clothing.
     
  6. Go to B19F and get a Violet Tail (Silver Fox).
     
  7. Hand over the Violet Tail directly to the Armoroad Shopkeeper.

• Hunt for the Porcelain Lady
  
• Hunt for the Abyssal King - Both missions share the same (BOSS) location at point E3.

Cyclopean Haunt
Reached the Sixth Stratum.


No quests are listed under this section. All post-game quests have been sorted under their associated Stratum and specific floors.

• For 6th Stratum navigation, please refer to Zaraf's maps uploaded on GameFaqs[gamefaqs.gamespot.com]. Since there are no quests here, you can just focus on navigating from floor to floor.
  
• To catch and defeat the Abyssal God's tentacles, refer to section 167 of Zurcamos07's Guide[gamefaqs.gamespot.com]. (CTRL+F = "Tentacle")

Fine Tuning
Forged a weapon.



Take a Breather
Pitched a tent.


Surprise!
Encountered an enemy through mining ore, gathering plants, or chopping wood.


Sea's Bounty
Went fishing.


Out With a Bang
Sunk a pirate ship with your cannon.



Rest in Body and Mind
Let an adventurer rest.


A Valiant Effort
Retired an adventurer.


Filthy Rich
Obtained more than 250,000 Ental.


A Farmer team gathering on the 6th Stratum will earn you a ton of money within minutes. Consider:

• MAX Harvestry
  
• MAX Keen Nose
  
  Optional:
  
• CHOP/MINE/TAKE
  
• Double Crop
  
• To Market
  
• Rain or Shine
  
• Safe Stroll

Progressing Sea Exploration is required to get the Dragon-related achievements. The locations of the 3 dragons are listed under their respective floors (CTRL+F Dragon Quests).

Everything you need can be found on the Sea Exploration (V2) GameFAQs thread[gamefaqs.gamespot.com]. All credit for this post belongs to ThatSageGuy. Upon reaching the Aerial Forest/Floating Island, you will have done enough Sea Exploration to access the Elemental Dragons and the achievements tied to them. The logical progression of food supplies, ship parts, and islands can be surmised from post #2.

Crushing Blow
Dealt 10,000 damage with a single hit outside of oceanic quests.


Cataclysmic Force
Defeated a boss in a single turn.

Bizarre Monsters
Defeated all types of Pasaran, including Gold, Red, and Blue.


There are a total of 7 Pasran variants:

• 1 for each of the first 4 Stratums (different poses).
  
• Blue Pasaran can be found on the 5th/6th Stratum
  • It summons a Red/Yellow Pasaran when receiving a non-fatal elemental attack of the same type.

Tips:

• Pitching a tent increases the chances of a Pasaran spawning.
  
• Upon defeating a Pasaran, rest for 14-15 days to allow a new one to spawn.
  
• Pasaran can go through walls. You can quicksave before heading to them in case you get unlucky with their pathing (especially in the 5th/6th Stratum).
  
• If you're not sure which variant(s) you are missing. Check the portraits on the Monstrous Codex.

Dragon Vanquisher
Defeated the Dragon.
Post-game boss

B4F point E1

Flower of the Sea
Defeated the Anemone.
Post-game boss

B5F point E1

Wyrm Vanquisher
Defeated the Wyrm.
Post-game boss

B11F point C6 after unsealing rocks at points C1, 4A, and D7

Drake Vanquisher
Defeated the Drake.
Post-game boss

B18F point B2

Abyssal Desire
Defeated the Deep Princess.
Mutually exclusive

After meeting Kujara on B11F and talking to both city representatives, pick up the mission Protect the Gatekeeper. This also unlocks the Yggdroid class further into the story.

Indistinguishable from Magic
Unlocked the Yggdroid class.




Porcelain Wish
Defeated Olympia and the Abyssal King.
Mutually exclusive

After meeting Kujara on B11F and talking to both city representatives, pick up the mission Slaythe Gatekeeper. This also unlocks the Shogun class further into the story.

Honorable Warrior
Unlocked the Shogun class.



To unlock the Eldest Path:

• Upon defeating Ketos and reaching the Deep City:
  • Promise not to reveal the location of the Deep City
    
  • Break that promise and tell Flowdia of the Deep City's location.
• Pick any side and progress that route storyline.
  
• After finishing Locating the teleporter, reaching B17F, and turning the mission in:
  • DO NOT accept the next mission.
• Get the 2 key items by talking to the Senatus members and a guard at the Celestial Palace. You can also do this after the next step but you can save the extra trip if you do this beforehand.
  
• Talk to the Eldest One (EO) on B10F point C4. Tell it that both your races can coexist.
  • The key items will turn into the Porcelain Offering.
• NOTE: There is no visible mission for this next part. Take the Porcelain Offering to the boss room of the 5th Stratum to automatically give it to the siblings.
  
• Enter through the Deep One door (TE) on B16F. It should be passable now.
  
• Follow this linear path which leads to the Progenitor.

Eldest Path
Defeated the Progenitor.
True End/Eldest Path

Starry Visitors
Defeated the Abyssal God.


Absolute Power
Defeated the boss of the Sixth Stratum on Expert difficulty.


In going for this achievement, I wanted to use the cheapest and laziest approach available to me. I wanted to see if I could get away with fighting this boss putting in the least amount of effort possible. After some consideration (and inspiration from Acea Ivalia's YT videos), I decided to use a H/Sov + N/G combination to utilize Drawing Slice while remaining under level 70.A few things to consider:

• I strongly suggest killing at least 4 tentacles.
  
• It's cheaper to gear 2 characters.
  
• Danda-chakra is faster and cheaper to Forge (compared to Futsuno Mitama) because you only need to kill the Ant Queen while it's asleep to get more Forging ingredients. It only has 2 free slots and a higher base attack too. This may not be the most optimal damage, but it's a lot faster to set up.
  
• I only used Books obtained from regular play (no farming involved). Vigor books went to the Protector.
  
• To farm the materials for some Strenth Ring(s), a Farmer team with max Waste Not will greatly speed up the process.
  
• Refer to the Abyssal God strategy page[etrian.fandom.com] for the move order at x number of tentacles during Phase 1.
  
• Phase 2 splits between Def/Atk mode. Avoid attacking during the Defensive mode to prevent counterattacks.
  
• Further explanations are in the page linked above but using this method the boss will be very predictable. You hopefully won't see the later rounds. If you want other more exciting ways to kill the boss, I highly recommend Acea Ivalia's YT videos.

Conqueror of Yggdrasil
Obtained all other achievements.
CONGRATS!!!

Thanks for reading up to this point! If you'd like, check out my other guides: https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=2987673258 https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=2990523519