A (Definitive Edition) guide to defeat the Telethia (Xenoblade X)
Hi all. I know that XDE has been out for over a year now and so this post probably won't be all that useful, but when you Google "Xenoblade X Telethia guide," this reddit post for the original game remains one of the top results. And for good reason - It still is THE best, most comprehensive guide on how a casual player can defeat the Telethia with the least effort possible. But the DE has changed the endgame grinding quite substantially, and so I thought it would be useful to make a post that maybe somebody, someday will find helpful. I also have a different suggestion for a Skell that IMO is easier to work with. (I also want to shout-out this other reddit post on farming Skells that I found very useful for finding item drops with the correct traits.)
As the other guide does, I assume that you are in a post-chapter 12 state.
There are two main changes that DE brought with it when it comes to endgame grinding.
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Material Ticket economy
If you have Nintendo Switch Online, it is trivial to obtain material tickets once you hit endgame. There is never a reason for you to farm a material for Skells or augments - It is always faster to farm tickets and purchase materials. Essentially, how it works is that you recruit BLADEs from other players, level them up to max level, and then dismiss them to obtain a fat stack of reward tickets. Some players have also set up their avatars so that you get Bonjellium when you dismiss their recruited avatar as well, a FronteirNAV material that is needed for most endgame augments. See this video by Enel for more details.
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Heroic Tale
Heroic Tale is a Photon Launcher art that is obtained by completing Neilnail's second affinity mission. It increases the level of an enemy by 5 or 6; An increase of 6 is guaranteed if the secondary cooldown effect is active (which, fyi, also happens if you use Quick Cast to cast an art that has its secondary CD bar at least partially filled).
The reason why this is so important is because the level of equipment drops is based on the level of the enemy when you defeat it. The highest tier for Skell equipment is guaranteed if the enemy is level 61+, but in the original XBX, there were many pieces of gear that had no easily farmable enemy of that level. So, in the original X, you were forced to kill a level 56 enemy and hope that it gave you a highest tier Skell drop, while most of the time you got a lower tier. Now, you can use Heroic Tale on a level 55 enemy to turn it over the 61 threshold and guarantee a high tier drop. This lets you farm high tier Skell equipment without gouging your eyes out.
A bit of a word on Skell gear nomenclature: For most gear, x60 is the highest tier, while x50 is the second highest. For example, a 460GG Phoenix is stronger than a 450GG Phoenix, despite both being "level 50" in the game.
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What Skell?
I recommend a thermal-focused Lailah Queen. This is a classic build from the original X, and it remains extremely effective even in DE. The main advantage of Lailah Queen is its overdrive that grants it health regen, debuff immunity, and lower damage taken, which makes it incredibly tanky during overdrive. It can also hold a max TP of 6000, meaning that you can easily "chain" overdrives into each other (start with 6000 TP, activate OD, OD ends and you have 3000 TP, activate OD, refill TP back to 6000 during the second OD, OD ends and you have 3000 TP, repeat).
The other main advantage of the Thermal Lailah build is that it uses weapons that have high hit counts. This is useful for quickly burning through the Telethia's 100 Decoy stacks during its third phase.
Finally, its just EASY. Literally all you do is sit there in overdrive and swap between your two sidearms. Sure, the fight takes a while because you can't 1-shot the Telethia, but for the amount of effort it takes to make, the thermal Lailah has so much bang for your buck.
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Farming Tips
Just in case you haven't figured this out yet: You can farm in X fairly efficiently by using "Return to Skell" on your map. This reloads the area and respawns the enemies, and you can choose exactly where you park your Skell. So its easy to kill an enemy, exit the Skell, open map, click "Return to Skell," and then bam, enemy has respawned and you can kill it again.
You also want to have a total Treasure Sensor rating of 100 to guarantee gold chests. This can be achieved by putting a full set of level 55 C&C shop gear on your characters, assuming C&C AM level of 5. Each piece of gear has Treasure Sensor VI on it - That's 30 points per NPC party member. You can then craft a single Treasure Sensor X aug and put it on any character to take you from 90 to 100.
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How to Build
Now, to walk through the actual building process.
First off is actually getting a Lailah Queen. It costs a bit over 4,000 reward tickets if you are buying every material from scratch. If you have been playing the game regularly and collecting your login bonus, you may have that much on hand. If you don't, just buy the strongest Mastema and Phoenix shoulder weapon you can from the shop, and then farm the alligators for tickets using the method linked in the video earlier. We're going to keep Lailah Queen in its default armor, which is pretty good.
Second, you want a 460GG Phoenix to speed up material ticket farming. You can get this by farming the Coffin Puges at the Old Ceremonial Hollow in Cauldros; There are 3 of them in one of the tunnels, and you can use Heroic Tale on them to get their levels to be above 61+.
Third, you want to build 3x Thermal Damage Up XX augments for the Skell frame. You will use these when killing the Telethia, but we're getting them early so that you can speed up farming.
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Fourth, its time to farm weapons. This gets its own little section because of how long it is. For all weapons, you want the x60 version of them. You want them to drop with particular augments though, and this is where the farming time comes from. Diskbombs are going to be your main source of damage, but you want the x60 versions of all of your weapons for higher level traits.
Sidearms: Diskbombs. These are by far the most important part of the build, as these are the main source of damage. You are looking for one with the WP-MSL-MAG trait - This is absolutely CRITICAL, as it makes the Diskbombs TP-generating monstrosities. You can farm them from Milsaadi. The best spot is to go to the Cavernous Abyss in Sylvalum, and fly about halfway down the shaft to the tunnel with the downed helicopter. 3x Milsaadi will spawn there, all with levels in the high 50s, meaning that you can Heroic Tale them to 61+. Even though this guarantees 260 Diskbombs, the Mag Up trait is sufficiently rare that this will most likely take the most farming time.
Back weapons: You can just keep the 460 GG Phoenix if it has a thermal or ranged attack up trait. Technically you're better off using 2x back weapons with Thermal Up traits instead, but I feel like that's overkill. Maybe if you have some x60 thermal back weapons with Thermal Damage traits lying in your inventory you can slap them on.
Shoulders: Sakuraba M-Missiles. These weapons with the WP-MSL-MAG trait are THE best weapons in the game by far for farming materials from enemies, although with the material ticket farm strategy, that's not necessary anymore. Still, they are very useful to have as they are high hit count weapons to help burn through the Telethia's Decoy, and also are thermal. So, I'd shoot for ones with the WP-MSL-MAG trait, but if you can't get one and instead get a Thermal Attack up boost, that's fine; You don't need to go insane farming these guys like you did for Diskbombs. You can farm these by using Heroic Tale on the Pugiliths in the Ganglion Antropolis. Note that access to this area requires completion of the Definian Downfall side quest, which in turn has a whole slew of pre-requisites. There are 4 Pugiliths to farm here: Start by running across the bridge on the right side of the main room, then dropping down to farm 2 in the pit, and then finally kill the 4th on the ramp heading up. Unfortunately, you need to kill these on foot, since a Skell can't fit in this area. Ideally, you are looking again for the WP-MSL-MAG trait again to help you burn through Decoys faster.
Arm weapons: Needlegun or Minigun with Ranged Attack damage traits. You can farm both of these from Caesar, the Hundred Eye in Stonelattice Cavern in Primordia (you should be able to kill him SUPER quickly in your Skell at this point).
Spare weapons: 360ME Crackers with Thermal Attack traits. You can farm these by using Heroic Tale on the Quos in Quay Hollow in Sylvalum. Note that you'll need to kill a Xe-Dom tyrant each refresh, but he should go down quickly at this point.
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Fifth and finally, its time for augments.
- You should already have 3x Thermal Damage XX augments on your frame.
- I'd recommend 4x Ether Resist XX and 1x Electric Resist XX augments on your armor (following the Least Effort Guide).
- For weapons....honestly, at this point, you're good to go. If you REALLY want to give yourself an edge, you can start slapping Ultrafauna Slayer XXs on your weapons until you get tired of ticket farming.
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And.....there you go, that's the Skell. Other than the Diskbombs, everything shouldn't take long to farm. You should be all set to take down Telethia, and basically every boss you can fight in a Skell other than Pharsis. As I mentioned at the top of the post, the strategy is simple: Go into the fight with 6000 TP, immediately pop overdrive, and then just shoot your Diskbombs and re-activate overdrive whenever it runs out. Your Diskbombs cooldown continues to decrease even when its not in use, so the strategy is "fire sidearm 1, swap to sidearm 2 and let it fire, then swap back to sidearm 1 until it fires again, swap to sidearm 2 and let it fire...." If you get unlucky and eat some damage while overdrive is down, maybe pop a frame HP restoration item.
Phase 1 is in the air, then it'll descend to the ground for Phase 2. Its immune during this transition, and it'll land in the same spot each time, so you can just go there preemptively and wait if you want. For phase 3, it'll fly back into the air again and then activate its 100 Decoy stacks. You then want to burn through those Decoys ASAP, so use your missiles in addition to your Diskbombs - You don't gain TP while burning through Decoy, so this is the one potential sticky situation you can be in if overdrive ends at an unlucky time while you're burning through the stacks.
But yeah, that's it. The fight itself is super straightforward. I know that this guide was long, but I wanted to have all of this information in one place, since it was scattered across various sources when I did this a few months back. I know it won't be helpful for most people at this point, but I hope that someone finds it helpful in the future!