As one of the two main characters of the game, Claude is, understandably, one of the stronger party members in Star Ocean The Second Story R. Stick him with the swords that you find in dungeons or purchase in stores and he'll do just fine for the entire game. If you want to make Claude by far the strongest character, though, you'll want to look into the Aeterna. It's a stupidly powerful weapon that will help you steamroll almost every enemy.
This guide will help you acquire the Aeterna in Star Ocean The Second Story R. It is not something you can get if you've already passed a specific portion of the game, so if you're already completed the Lacuer Armory Contest and Linga you'll need to wait until another playthrough. If not, read on.
Step 1: Complete the Lacuer Armory Contest
Whether you're playing as Claude or Rena, the first step in this process is making it to the final match of the Lacuer Armory Contest. If you're Claude, you'll need to fight three battles, solo, and win them all. Get Claude to level 22 or greater and this should be a piece of cake. If you're Rena, you just need to ensure that an AI Claude is strong enough to win one match. Level 22 should still suffice.
The final match will see Claude lose to Dias, regardless of how strong you are. That's fine. All you need to do is fight him.
Step 2: Acquire the Deadly Edge
Once the contest is over and Lacuer returns to normal you'll need to make a trip to the home of Gamgee, the blacksmith who made Dias's sword for the contest. He lives on the west side of Lacuer City. (You'll know his home well if you're playing as Rena.) Enter the house and Gamgee will give you the Deadly Edge, a gift from Dias for doing so well.
The Deadly Edge on its own is a so-so weapon. Good for this point in the game, but it will quickly become outclassed. That said, you must have the Deadly Edge to get the Aeterna, because we're going to be turning the Deadly Edge into the Aeterna.
Step 3: Acquire Mithril
In order to convert the Deadly Edge into the Aeterna you'll need two pieces of Mithril, a rare crafting material. There are various ways to acquire Mithril:
- Level up the ESP Skill - each time you do your characters will receive a random item, which can include Mithril
- Activate the Survival Specialty (Resilience + Herbology) - you'll randomly receive items while you walk around, which may include Mithril (not recommended, as it takes forever)
- Transmute Iron into Mithril via the Alchemy IC - requires the Lezard Flask from Centropolis
- Complete Alchemy Missions (I'm not sure which ones yet, but I've read that you can do it - once I find out which do the trick I'll edit this)
- Complete the 'Reach Customization Lv. 10!' Expert Challenge Mission, which gives five Mithril as a prize - this requires a lot of SP
- Coplete the 'Reach Blacksmith Lv. 10!' Specialist Challenge Mission, which gives three Mithril as a prize
- One piece in a chest to the northwest of the Hoffman Ruins - you'll need the Bunny Call Super Specialty (two characters with Familiar + one with Scouting) to climb the mountains in your way
- Enemy drops (in one of the trials on Energy Nede, I believe - I'll need to verify this)
I highly recommend using the 'Reach Blacksmith Lv. 10!' reward for completing this step. Getting the Blacksmith Super Specialty to level 10 requires a fair amount of SP, but you can spread it out over your entire party, and it's an overall handy ability throughout the game. This also encourages your characters - including Claude - to learn Customization, and you'll need that for the next step.
Step 4: Customize the Aeterna
Now that you have the Mithril you need to use it alongside the Customization Speciality to turn the Deadly Edge into the Aeterna. Customization requires the Eye for Detail, Smithing, and Aesthetic Design Skills, and is most successful under someone with the Originality Talent. Claude has Originality, and since characters can only Customize their own weapons...
Ideally you want to raise Claude Customization Specialty as high as you can get it, and Level 10 is the optimal peak. Unfortunately, this requires a lot of SP, as Aesthetic Design alone incurs a substantial price with each new level. Get Aesthetic Design up a few levels, then bounce back and forth between Smithing and Eye for Detail to reach subsequent levels. You need to get Claude Customization to Level 7 at a minimum to successfully forge the Aeterna.
Get to work once you're ready. The first step is to Customize the Deadly Edge into the Blade of Minos. The Blade of Minos is a powerful weapon in its own right, but it also damages Claude with every swing. Not great. (Though if you want to level, equipping the Sword of Minos can help... so long as Rena heals Claude the whole time. Make sure you unequip the Sword of Minos before moving on to the next step.)
Once Claude reaches Level 7 in Customization you'll have a 10% chance of forging the Aeterna out of the Blade of Minos. Save your game before you try, then reload if it doesn't work out. You have one chance to get the Customization right, so you'll need to be quite patient (unless you get lucky). Eventually, with enough persistence - and a lot of careful reloading - you'll Customize the blade.
Success! You now have the Aeterna. In addition to being ridiculously strong - the Aeterna has a base Atk of 1,600! - this sword has a special ability. Whenever Claude hits an enemy the Aeterna sends out a little spray of sparks which can hit the original target or any other, nearby enemies, dealing extra damage. You will absolutely decimate most enemies while wielding the Aeterna, which nullifies much of the challenge of Star Ocean The Second Story R. You can keep this thing on Claude all the way to the post-game dungeon, if you like. Enjoy!
(Suffice it to say, I won't be using the Aeterna while writing this walkthrough. I've had fun with it in the older games already.)