Any% Walkthrough

Phantasy Star III can seem like an intimidating speedrun to attempt at first, but after getting through Rhys' Generation, the remainder of the game is actually easy enough.

Resources: Maps, item information, and monster information can be found here: http://ps3.huguesjohnson.com/

NOTE on running: Early in the game, getting caught while running can either cost you a lot of time or cost you the run in general. A good rule for beginners is to fight if you feel you can kill the enemies in two rounds and run if your HP is low or if you feel that the enemy will kill you before you can kill them. It is something you will learn with experience playing the game. Also, until you get Wren in your party, fights can be extremely dangerous. Once you get Lyle things are a bit safer.

Also note that this is more or less a safe route and is no means the fastest possible route right now. As you play more of the game, you will become more and more comfortable with what works for you and what doesn't.

Rhys' Quest: 
NOTE: No matter which category you are running, this part of the run will most likely be the same. The only difference would be the amount of Escapipes you have on hand.
1. Time starts on control of Rhys. Head left to the item shop. Sell Rhys' Boots and buy an Escapipe.
2. Head to Landen Castle and go through the marriage sequence (all automatic once you enter Maia's room) until you are thrown into the dungeon.
3. Pick up the Knife, 300 Meseta, and Monitor.
4. Move towards the gate, but not directly against it. You can talk to Lena a few pixels away from the gate. PRESS UP as you talk to her. After the conversation with Lena ends, if done correctly, Rhys will move up and will not follow Lena. At this point, mash the C button (Menu) until you can access the Menu. Use the Escapipe.
5. Go through Landen Dungeon, picking up both Dimates (for use later, do NOT use any Dimates unless an absolute emergency) and the Trimate (to sell later). Exit through the stairs closest to the 2nd Dimate.
6. Enter the Dungeon again and take the stairs in the southwest corner (the one that leads to the Technique Shop). This will trigger the remainder of the escape cutscene and Rhys will automatically exit the shop. (NOTE: if you do not trigger this scene, Lena will not show up after the Lyle fight).
7. Walk straight to Ilan, running from every battle.
8. In Ilan, go straight up to the back wall and talk to the man near the exit. He will mention that he saw one of Laya's people near a lake and that she never blinked (this will trigger Mieu to show up).
9. Go northeast from Ilan to the lake and recruit Mieu.
10. Walk to Yaata, still running from enemies.
11. Sell the Trimate and Knife. Buy 3 Monomates and 2 Antidotes per character (100 Meseta). Can buy more if you feel uncomfortable but make sure you have at least 450 Meseta remaining.
12a. Buy 2 Hunting Knives for Rhys and a Claw for Mieu (440 Meseta). EQUIP THEM
12b. Rest at the Inn if HP is low. Save if you wish, though remember that saving does eat time (as you get better with the game, you will feel better about saving less).
13. Talk to the Old Man near the fountain at the east side of town. This will cause you to exit town near the boat. Enter the boat.
14. Fight every enemy in the Island Cave. Enemies here give good amounts of Meseta for this point in the game.
15. Grab the Escapipe, Dimate, Antidote (optional, but it's there if you are low), and talk to Lyle for the Sapphire. 
16. WALK (do not use the Escapipe) out of the cave. Continue to fight for more Meseta.
17. Heal in Yaata if need be, then take the cave to Aquatica.
18. Buy Mieu a Hunting Claw (OPTIONAL) in Rysel. Restock with about 5 Monomates/2 Antidotes per person. Heal/Save if need be.
19. Go south to the hidden passage to Aridia, grabbing the Dimate and Antidote on your way. 
20. Go to Hazatak and buy a Sword (OPTIONAL, but recommended for beginners) for Rhys (510 Meseta, sell Hunting Knives if need be). Restock/Heal/Save if needed.
21. Go to the Western Cave and get Wren (the Escapipe in the chest is optional but is slightly out of the way, so it could be dangerous to get it at this point). Put Wren in front (as a meat shield as he will be useless for a bit otherwise) and use the Escapipe you got from the Island Cave.
22. Rest in Hazatak, buy an Escapipe (unless you grabbed the one from the chest in the Western Cave), and go to the Control Tower. On your way, burn up Wren's TP so that you can take advantage of the Free Win glitch if you ever get first strike on an enemy.
23. Take the 2nd stairway you come to and go right a bit to the Trimate. Return down and recruit Lyle (put him behind Wren and give his Boots to Rhys). Fix the Weather Control. Take the stairs to the south and grab the nearby Trimate. Escapipe out.
24. Go straight to Aquatica and to the town of Rysel. Buy a Steel Armor for Rhys (OPTIONAL, but recommended for beginners).
25. Take the boat and go to Shusoran.
26. Rest/Save and enter the dungeon through the fountain. 
27. Grab the nearby Trimate and exit. 
28a. Start selling items at the weapon shop. You need 1500 Meseta here to get the Ceramic Shot (1300 Meseta) and some possible supplies (unless you haven't used too many). Start with the Trimates (750 Meseta), then any equipment you don't need anymore (old Claw, Hunting Knives, Lyle's Staff/Garments, Mieu's Ribbon/Vest). If you still don't have enough Meseta for the Ceramic Shot, go outside and grind until you have enough for the weapon and some supplies (Rhys should have at least 4 Dimates). Also, if you skipped buying a Sword and Steel Armor earlier, buy a Steel Sword for Rhys. If you have the money left over, don't bother selling the Hunting Knives as those can be given to Lena later.
28b. This next step is a matter of preference vs. safety. I personally like Rhys to have about 55+ HP for the upcoming fight against Lyle, but it is possible to be lower. He usually will be around that at Level 9, but it is possible with good luck and strong stat gains to win the fight as low as Level 6 or 7. Because of the randomness of stat gains and the RNG in the fight, if you are going for WR then having lower levels will most likely save you time. However, the more levels you have, the safer the fight will be and the better your chances of completing a run, but at the same time, having too many levels mean that you will out-speed Lyle, which can be detrimental when wanting to heal.
29. Rest/Save. Distribute Lyle's techniques to favor Zan, then enter the Shusoran Dungeon again. Go through until Lyle leaves the party.
30. Talk to Lyle again to start the fight (Rhys will automatically be healed to full HP for the fight).
31. This is the biggest gateway of the game. Lyle has two attacks he can do. A normal attack will deal anywhere between 13-18 HP damage whereas Zan will range from 23-32 damage. Attack the first turn, then react accordingly. An ideal pattern is attack, heal, attack, heal, attack, heal, attack, though if you are somehow faster than him, you can possibly attack, attack, heal, attack, attack. Use your best judgment and heal whenever you get close to 30 HP. It will take about 4-5 attacks to take Lyle down.
32. Talk to Lena. Remove her knife and rearrange the party (I like the order of Wren, Lyle, Lena, Rhys, Mieu). Rest/Save in town.
33. Return to the Control Tower in Aridia and fix the Satellite Control Machine. Escapipe out..
34. Go to Rysel in Aquatica. Stock up on a ton of Monomates and about 2 Antidotes per person. Redistribute Mieu's Order Techniques to favor Fanbi and her Heal Techniques to favor GiRes. Also, make sure that Wren OR Mieu has 4 Escapipes.
35. Go to Cille. Rest/Save. Enter the 3rd fountain from the left.
36. Make your way to King Cille (when using Healing Items, start with the ones Lena, Lyle, and Rhys have. Try to save as many healing items from Mieu/Wren as possible). Also, try not to use Mieu's techniques if possible.
37. Fight King Cille. Zan/Ceramic Shot on the Dryads should eliminate them. Have Mieu use Fanbi on Wren and Rhys should attack/heal when need be. King Cille can use a normal attack or Zan. Mieu's GiRes should heal most of the damage from Zan. If Lena is still alive and has healing items, she can heal, else just have her defend. King Cille should go down quickly.
38. When given the option, choose to marry LENA.

Nial's Quest:
1. As soon as you get control, use an Escapipe. This will teleport you to the entrance of Cille Dungeon.
2. Go through the dungeon (the only encounters are Chirpers) and then through the castle. If you wish to, give Nial a couple of Monomates so that he can provide backup healing if in a bad situation. Talk to King Cille again.
3. This fight will be a bit slower, but still easy enough. Fanbi on Wren, have Wren and Nial attack. Mieu should react with heals accordingly. Other than that this fight is a straight DPS race and should be okay. 
4. When given the option, choose to marry ALAIR. Choosing to marry Laya will create a softlock.

Aron's Quest:
NOTE: Though you have many of the key items, the Sub Parts, Mystery Star, Twin's Ruby, and Laya's Pendant DO NOT work because the game checks for certain triggers in the game instead of the actual item itself. This means that you will have to get those items manually in this quest. Also, rest at your discretion.
1. After you gain control, enter the Dahlia dungeon and EXIT it again. Entering again will reset the Escapipe point to that stairway, otherwise the Escapipe point will remain at Cille which will indeed softlock the game.
2. Pick up any of the equipment on your way to the Aero Parts (giving the Laconian Gear to Wren). Mieu, Wren, and Kara will gain levels fast enough but the fights can still be dangerous. Aron should be able to easily survive and his heals are very good with a large TP pool. You should be fine, but beware because if you die here, your last save was most likely back in Cille.
3. Use an Escapipe once you have the Aero Parts. 
4. Take the shuttle back to Aerone. Rest/Save and leave town.
5. Fly towards the Rebel Cave to the west and grab the Sub Parts. You could also grab the Laser Claw if you want Mieu to have a bit more attack). Escapipe out.
6. Fly to the northeast of Elysium and go through the cave to Landen.
7. Fly closer to the cave to Aquatica and go through that cave.
8. Go through the cave to Aridia.
9. Hug the right side of the river near Hazatak until Wren turns into a Submersible. Recruit Laya. Return to Hazatak.
10. You need 3 Escapipes. Buy until you do.
11. Take the cave to Frigidia.
12. Go east to the airport and fly to Mystoke. Buy Mieu a Royal Vest and enter the castle.
13. Go through the castle until you get Laya's Pendant. Escapipe out.
14. Rest/Save. Fly to Skyhaven.
15. Enter the dungeon and grab the Aqua Parts. Also, it is probably a good idea to grab the nearby Royal Crown for the extra Meseta later. Escapipe out.
16. Taking the temples, go to Elysium and then to Landen. Go to the nearby pier and go to the sunken temple to get Orakio's Sword.
17. Take the temple to Aridia. North of Hazatak is Miun walking about. Talk to her to get Miun's Claw.
18. Take the temple to Aquatica. Fly to the island south of Sage Island then switch over to the pier and sail to the island.
19. Grab every treasure in this cave on your way to Siren. Talk to him to get Siren's Shot. Finish collecting the treasure and then talk to the bottom-most sage to learn the Word of Power and to teach Mieu the Grantz Technique. Escapipe out.
20. Make your way to Frigidia and fly to New Mota.
21. You now have a decision to make as to whom you want to power up with the Pron Glitch. Either Kara or Laya are decent choices, but it is generally a good rule to pick whomever has the lowest agility. Whomever has the lowest agility of the two, sell off their equipment and give their weapon to either Aron, Mieu, or Wren for a while. Normally, I would hope that Kara would be the one to choose as having her attack first would be awesome.
22. Sell off any of your unneeded equipment. If you are not glitching Laya, give her the Laconian Crown. If you are not glitching Kara, give her the Laconian Bandanna. Buy a Planar Claw for Mieu and a Planar Slicer for Kara (if you are glitching her, just have someone else hold it for now. Rest/Save.
23. Fly to Skyhaven. Make sure that whomever you are glitching has NOTHING in their inventory, else the powerful Pron Glitch will not work.
24. Talk to the 2nd Sage in line to power up the legendary weapons into the Nei Weapons. The game will act like it is frozen for a moment, then you will get some glitched up sprites and whomever is in the back of the party will be offset a bit.
25. Check the stats of the glitched character. Hopefully their Speed is close to 240 or 250, meaning they will most likely always go first in battle. Their Attack and Defense will also be high. While this doesn't do anything with how much damage they deal in battle, this character will take 0 damage from all physical attacks. 
26. Place your glitched character at the front of the party and equip everybody with their new weapons. Everyone's gear should match or be close to below (what they have on their feet doesn't matter).

Aron: Nei Sword, Laconian Helmet, Laconian Armor
Nei: Nei Claw, Planar Claw, Ribbon (maybe), Royal Vest
Wren: Nei Shot, Laconian Gear
Kara: Nei Slicer, Planar Slicer. If unglitched Laconian Bandanna & Steel Robe
Laya: Nei Bow. If unglitched Laconian Crown & Fiblira

27. Fly to Mystoke. Buy Trimates until everyone has a full inventory. If enough money is left over, you can buy Wren a Royal Protector or an upgrade armor for either Kara or Laya, but it doesn't matter.
28. Redistribute everyone's techniques to favor GiRes and Fanbi.
29. Rest/Save. Fly west close to the temple and take it to Terminus.
30. Fly to Lashute. 
31. Make your way to Rulakir. Heal with Trimates when HP gets low, or have Aron use GiRes. Save the TP of your glitched character for GiRes during the final battle.
32. Rulakir should go down easily. Use Fanbi on Mieu, GiRes in reaction to Tsu (Kara and Laya are good at this) and he should go down easily.
33. Make your way to the chest with Dark Force. Heal fully before opening.

Turn 1: Aron and Wren attack the Left Hand (the one on the right side). This is the healing Hand but only has 300 HP, so one turn should kill it. Mieu, Kara, and Laya should all use Fanbi on Mieu.
Turn 2+: Heal with GiRes with your glitched Character whenever Dark Force uses Tsu. Aron and the non-glitched should heal through Foi. Otherwise, Aron should attack the right hand with Wren. Any free turn should be used casting Fanbi on Mieu and Mieu attacking the body. Keep stacking Fanbi on Mieu and heal accordingly. Dark Force should fall very easily.

34. Time ends (from what I understand) once the cutscene with Lashute's destruction ends and you see the Alisa III's cutscene.

LadyErianna

Phantasy Star III: Generations of Doom

Sega Genesis

Quarbit

USA / NTSC

Adan

Aron

Crys

Sean

Genesis

Characters

Turbo Controller?

Version

Wii Virtual Console

Game Boy Advance

PlayStation 2

PlayStation 3

PlayStation Portable

Xbox 360

PlayStation 4

Xbox One

Switch

Phantasy Star

Different Versions + Inventory Underflow list

Discord

New Glitch... useless for now

Damage Calculation

Inventory Underflow (GBA)

All Generation/category naming.

Adam_ak

Jiseed

TheSPER