You may have reached this page directly from the walkthrough / strategy guide coming from the Deep Sea Research Center. If so, this next section is a continuation of the discussion about whether or not you should continue to the bottom of the Deep Sea Research Center or whether you should leave this farming spot open so that you can continue to defeat as many Tri-Faces as needed.
Note that once you reach the bottom of the Deep Sea Research Center and defeat Ultima Weapon (and Draw Eden from it), you can no longer utilize this trick. The Deep Sea Research Center, which was previously full of dangerous enemies, will no longer have any enemy encounters at all once you have defeated Ultima Weapon.
The important element of this though is that you technically don’t need to defeat Ultima Weapon at all. There are no rewards for doing so that you can’t obtain elsewhere. But lets delve deeper into that first. What are the rewards for defeating Ultima Weapon?
Eden Card at the end of the battle.Both of the above rewards can be obtained through other means at the end of the game. More specifically, you can Draw Eden from Tiamat while you are completing the last dungeon of the game in Ultimecia’s Castle.
Additionally, you can win the Eden Card from the CC-Group card members (specifically the Princess Diamond twin). Check out the Recovering Lost or Refined Cards section for more information.
The main purpose for leaving Ultima Weapon alive is to continue utilizing this trick to battle against Tri-Faces is because they have a chance to drop a raw material, namely a 
Curse Spike. You can also steal Curse Spikes from them while in battle using Mug which is definitely a much more efficient means of collecting them.
Curse Spikes are an incredibly valuable item. Each Tri-Face that you fight has a chance to drop some (among a myriad of other items) or you can successfully steal Curse Spikes from them every time you encounter them in battle. Why are they so important?
To start, you will need 2 of them to create Selphie’s most powerful weapon, Strange Vision. But this is just a one-off item. 100 Curse Spikes can be refined into 1 Dark Matter using Siren’s 
Tool-RF. Dark Matter has the following properties:
Ultima Stone using Bahamut’s Forbid Mag-RF which then can be refined into 100 
Ultima Magic. This is the most powerful magic in the game (and makes an excellent Junction to any stat).Shaman Stone using Siren’s Tool-RF ability and the Shaman Stone can be refined into a Dark Matter using Eden’s GFAbl Med-RF ability. 
Rosetta Stone are very powerful items that can teach a Guardian Force the 
Abilityx4 ability, allowing your characters to use more of the GF abilities available to them.Luck-J Scroll using Eden’s GFAbl Med-RF and this can be refined into Luck Up using Doomtrain’s Forbid Med-RF ability. This is one of the only means to crank up a character’s Luck stat and the only efficient way to do it if you are planning to play a “perfect game” (all characters to their maximum stat level).The fixed encounters are triggered in the bottom section of the Deep Sea Research Center, after you have gone down through the Steam Pressure system. Refer to the Deep Sea Research section for more information on how to navigate down to the right area. Note that the guide will warn you when you’ve reached the Fixed Encounter section:
At this point you should have reached the bottom sections of the Deep Sea Research Center, had Zell open the final door for you, and be near the Save Point. There are three spots in this area where an encounter will trigger against a Tri-Face.
One near the Save Point, one near the middle of the walkway going down the stairs, and the last one near the bottom of the stairs. Each time you leave this area (either through the top or bottom) and return, the encounters will have been reset and you can battle against 3 more Tri-Faces.
Tri-Faces are extremely annoying. Make sure that you have Diablos’ 
Mug ability equipped to one of your characters as the goal during each of these fights is to Mug Curse Spikes from each Tri-Face before you defeat it.
Note that Bahamut also has the Mug ability but probably does not have it learned yet, so make sure that you have Bahamut learning it as quickly as possible. Having two opportunities to Mug a Tri-Face can greatly speed up this process.
The most annoying aspect of fighting against a Tri-Face has to do with one move that they use called Poison Gas. This has the potential to inflict a number of negative status effects including 
Poison, 
Silence and 
Confuse.
Confuse is the most frustrating of these ailments so consider ensuring that each of your characters has Confuse junctioned to their ST-Def-J abilities. Esuna also helps improve resistance to status effects across the board.
Aside from that, the biggest tips that can be offered for this section of the game are to be very liberal with saving your game at the Save Point, just in case you get unlucky during a battle, to use your stockpile of 
Remedy on team members with negative status effects, and use 
X-Potions (and Tents when you’re at the Save Point) to keep your characters HP topped off.
Keep 
Enc-None on the entire time you are in this area as the fixed encounters will initiate regardless of whether you have this equipped or not, allowing you to avoid other unnecessary battles that aren’t helping you stockpile Curse Spikes. You may also want to consider using 
Initiative to help yourself get in and out of battles quickly.
Don’t forget that if you are playing the more modern PlayStation 4 or Steam versions of the game that you can speed things up by pressing in the left control stick. Just be careful though as things can spiral out of control fairly quickly - be ready to turn it off quickly!
So how many Curse Spikes do you need to farm?
The following list are just suggestions to give you some sense of how long you may want to farm in this area. Obviously if you are going for a perfect game you will need to just not defeat Ultima Weapon or obtain Eden from the Deep Sea Research Center at all, but for those players that are not playing the game trying to fully max out every stat, use the following chart to help you make a decision.
Keep an eye on the number of Curse Spikes in your inventory. You can’t hold more than 100 so you should immediately transmute them into a Dark Matter as soon as you hit that number so as not to let any of them go to waste.
Here is a chart to help you decide how many Curse Spikes to farm and in what order you may want consider using them:
| Usage | Curse Spikes | Refined Into | Running Total |
|---|---|---|---|
| Selphie’s Strange Vision | 2 | (None) | 2 |
| Quistis’ Shockwave Pulsar (Blue Magic) | 100 | Dark Matter |
102 |
| Rosetta Stone |
100 | Shaman Stone |
202 |
| Ultima |
200 | Dark Matter x2 |
402 |
| Luck Up |
(until stats maxed) | Luck-J |
X |
* You may have already constructed this item and have Selphie using it
As a result, even if you aren’t planning on playing a perfect game, according to the chart above, you may want to consider either farming 202 or 402 Curse Spikes. There are other places to obtain Ultima Magic and, in some cases, more efficiently than this. Therefore, at least 202!
You can return to the Deep Sea Research Center side quest page using the link below once you are done:
