Guide to EIDOLON SLAYING! (Incomplete, will be updated over time)

[NaughtyKat]

[UPDATED with input and additional findings]
[UPDATED again, with input from other commenters and my own new findings from two additional Eidolon runs]

Hello, I am starting this thread to report my findings on the Eidolon enemies so far in order to help fellow Tenno to defeat them more easily. This is my first forum post so I hope I am posting it in the right place and that its up to par. This is currently incomplete as I haven't survived a full fight with a Teralyst Eidolon yet but I will try to update it and I encourage all of you to add your own input to it. Notes in italics will be used to signify things which need further research.

Please also keep in mind that this post will contain indirect spoilers for The Second Dream, The War Within and Saya's Vigil (the Glassframe quest), so if you haven't completed all three of those yet I advise you not to read this yet.

 

DEFINITIONS

So first off let's define the terms we'll be using. Eidolons or Eidolon Sentients (also called Spectral Sentients) are a special new type of enemies only encountered in the aptly-named Plains of Eidolon at night. The Eidolons are worn-down Sentient drones, "fragments" of a dead Sentient who was slain in an ancient battle taking place on the Plains, like how the Oculysts, Conculysts and Battalysts are "fragments" of Hunhow. The Eidolon term refers to the fact that they are not fully alive but not fully dead either, and they also differ from other Sentient enemies we've encountered so far in that they don't seem to have the ability to adapt to damage types, possibly due to their "undead" state. They come out at night, with the goal of trying to re-assemble their dead master and neutralizing all who stand in their way. There are two types of Eidolons: the towering mecha-kaiju shown in the PoE trailers are called Teralysts, while the small hovering drones that accompany them are called Vomvalysts.

Another addition with the Plains of Eidolon update is the Quills syndicate, which can be accessed after completing all three afore-mentioned quests by walking up the side-trail to the right of the path to the main gate of Cetus and entering the door while in Operator form. They ascend the Tenno Operators into Warrior Operators and provide them with an Amp, a special modular weapon that can channel and enhance their Void Beams to deal more damage.

 

GENERAL INFO

The Teralyst Eidolon bossfight is probably one of the hardest content in Warframe so far, so it is highly recommended to tackle it with a full squad of four Tenno, all piloting well-modded Warframes, armed with the best Amps they can afford and wielding high-damaging primary weapons. If rifle-type weapons which rely on many low-damage shots to deal damage are used (such as Soma Prime or Supra), ammo refills should be brought due to the length of the fight. Alternatively, shotgun-type weapons which rely on few high-damage shots to deal damage can be used (like Tigris Prime or Opticor). It is not advisable to bring Kubrows or Kavats as they will not be able to deal damage to the Teralyst and will die easily. If you have access to the Archwing Launchers, it is highly advisable to craft them because the ability to fly will let you find the Teralyst more quickly as well as dodge its attacks more easily as some of them have slight homing abilities and others seem to be landslam AOEs. Another thing you should keep in mind is that during the night, stepping into any water, even shallow water, will deal damage and inflict the Magnetic debuff so it is best to avoid water entirely. It seems that the Teralyst shields are affected by the Shield Disruption aura but this may be a bug.

As for Warframes, a Trinity could be highly useful for her powerful healing and energy regeneration, and a Rhino could improve your squad's survivability as well by serving as a tank, especially combined with a taunt build such as the Guardian Derision mod. Crowd control frames like Banshee and Equinox could be effective agaisnst the Vomvalysts. Novas could be highly useful due to their wide array of abilities including crowd control and damage. A Frost's ability to create Snow Globes could be very handy for creating cover for your squad to shoot from.

It is entirely possible to fight the Eidolons, including the Teralysts, with a basic unmodified Amp and even slay them, but in the case of the Teralyst there is a time limit on the bossfight in the form of sunrise. If the Teralyst is not slain by the time the sun starts rising, the Teralyst will despawn alongside all the other Eidolons, and in my experience it is not hard for the fight to be drawn out to this extent if not properly prepared.

 

VOMVALYSTS

Small hovering Eidolon drones that spawn en masse in the Plains at night, especially around a Teralyst. They attack all Tenno on sight and can be lured in with the hackable Eidolon Lure drones found in certain Grineer mini-camps. They have two forms, and in their usual form they can be hurt by any Warframe weapon or ability as well as Operator Void Beams. Their second form is characterized by their entire body glowing bright blue and while in it they can only be damaged by an Operator's Void Beam (normal Void Beams will work but Amps deal more damage). They are not challenging on their own but they have strength in numbers and their ability to change forms can be disorienting. They seem to have an unknown chance to drop Sentient Cores, possibly of different qualities. The two tactics at your disposal for slaying them are to fire at them in Warframe form and finish them off by switching to Operator form, or by fighting them entirely in Operator form. It is probably only a matter of preference.

During the Teralyst's bossfight, the Vomvalysts have an additional role besides supporting the massive Eidolon with their own firepower. After the Teralysts's blue "shield" bar has been depleted, if they are nearby they will fire a glowing strand of blue energy at it and regenerate it, which can be a major hassle as it forces you to damage it again and they can repeat the regeneration indefinitely. They seem to only start doing this in the Teralyst's second phase. Killing them all does not seem to be a feasible solution to this problem since they seem to respawn indefinitely in the Plains at night. It seems that the only way to permanently disable this is to use an Eidolon Lure. If you have more info on this please post it.

 

TERALYSTS

Towering Eidolon bosses resembling giant mecha kaiju that spawn one per instance in the Plains at night, accompanied by a host of Vomvalysts. They will ignore the Tenno at first unless they get too close or attack. They are fought in several phases and can easily cause Tenno deaths with their overwhelming firepower. Their main health bar consists of a large yellow "armor" bar and small blue "shield" bar.  Each phase, the blue bar needs to be stripped away in Operator form before they can be properly damaged by Warframe weapons and abilities and move on to the next phase. Each time a phase is completed and a Synovia is destroyed, the yellow bar seems to be incrementally decreased, and they presumably die when it reaches 0. They possess an unknown amount of highly damaging attacks, most or all of which seem to be AOE. It is unknown whether they unlock more attacks as the phases go on.

At the start of a phase, they are invulnerable to damage from Warframe weapons and abilities, and they can only be damaged with the Operator Void Beams (normal Void Beams will work but Amps deal more damage) until the blue-tinted "shield" part of their health bar is fully depleted, which will initiate the second half of a phase. In my experience, with the basic unmodified Amps this is a rather slow affair and it is best to have a full squad of four Tenno all wielding Amps to achieve this in the shortest amount of time with the least casualties. It is possible we are meant to farm the Vomvalysts for Sentient Cores in order to upgrade our Amps before trying to engage the Teralysts, but I believe it is possible to beat the first phase at least with the basic unmodified Amps as well.

In the second half of a phase, they become invulnerable to all damage except in four areas called Teralyst Synovias, one on each arm and one on each kneecap, all of which have their own healthbar. Some of my squad members reported seeing a fifth Synovia on the head but I didn't, so this still needs to be confirmed. The healthbar is vulnerable to both Warframe weapons and Operator Void Beams. In my latest run, a player in the squad called DeathStalker1337 noticed that during the first phase, Operator Void Beams seemed to be doing more damage than weapons, but in the second phase weapons were doing more damage. It is possible that the Teralyst becomes less resistant to weapons as more Synovias are destroyed. After a Synovia is destroyed, in its place is a swirling orb of blue energy which doesn't seem to be of any importance. After a Synovia's health bar is depleted, the next phase will start. In my experience, these health bars are rather large, and it is probably advisable to again have a full squad of four Tenno and also for all of them to be wielding powerful and well-modded weapons.

After the first phase ends, the leader of the Quills speaks and instructs the Tenno to back away as the Teralyst unleashes an expanding wave of energy that seems to deal enough damage to one-hit kill any Warframe. The Teralyst then dissapears and the squad has to explore the map to find and engage it again. It is recommended for squad members to spread out across the map and waypoint the Teralyst when they found it so the others can regroup at that location as well. Presumably the phases repeat like this a fixed amount of times until all the Synovias are destroyed and the yellow bar is fully depleted, at which point the Teralyst presumably dies and drops its unknown loot (which would mean the Teralyst has four phases, or five if there's a head Synovia). However, me and my squads did not yet manage to beat the second phase (destroy the second Synovia) in time before the sun rose and the Teralyst despawned, in part because we were still figuring out the mechanics of the fight and in part because of the Vomvalyst interference. I encourage all of you to try the Teralyst bossfight for yourself if you have all the requirements for unlocking the Quills syndicate and to try to hold out longer than we did, and to post your findings here so they can benefit other Tenno. I will also report any other findings I come across here. I hope this can help at least some Tenno with this exciting and challenging new bossfight.

Edited October 13, 2017 by NaughtyKat
A lot of new information on the Teralyst bossfight added.

[Wikldash]

The only thing I would like to know is what are the orbs that drop when killing the Vomvalysts (though I think they are XP orbs for the Amp).

[NaughtyKat]

@Wikldash I'm not sure which orbs you mean, are you perhaps referring to the Sentient Cores? They look sort of like orbs, seem to drop from Vomvalysts in my experience, and you can trade them to the Quills for standing which you can in turn use to buy upgrades for your Amp and your Warrior Operator.

[Xaero]

I've noticed both beam and amp damage Teralyst in the 1st phase by shooting anywhere.

[NaughtyKat]

That's a good catch @Ksaero! I feel dumb not noticing it now, but I guess I was too focused on the "weakpoint" concept to even try shooting at the rest of the body lol. I'll update the post, and I'm also doing another run right now so I'll have a lot more to add soon.

[Aekhon]

Thanks for posting this; I saw the sentient core crafting requirement and was afraid you had to kill Eidolons to get amp equipment; now I know I've just been unlucky with the little guys.

[Xaero]

1 minute ago, NaughtyKat said:

That's a good catch @Ksaero! I feel dumb not noticing it now, but I guess I was too focused on the "weakpoint" concept to even try shooting at the rest of the body lol. I'll update the post, and I'm also doing another run right now so I'll have a lot more to add soon.

Is there any info on ways of farming Quills rep besides exchanging the cores? It just seems too slow and unrewarding.

[Althial]

I have just managed to kill an eidolon and oh my lord, it takes 10 minutes. First, all 4 players use your operator beam to kill it's shields, then aim for it's kneecaps or any other blue/glowy part of the body. I found that volt's 3 helped a ton with defense and offense, and also gave extra damage. Good luck Tenno! :D 

[Saml565656]

What about those lures for the Vomvalysts, what do they do exactly? I found that they absorb three or four Vomalysts when they are in the bright blue ghost mode. The sort of get sucked in but then I cant don anything with the lures except have then follow me around. 

[Wikldash]

@NaughtyKat there are 2 orbs that drop from the small guys one is the core and the other is a ball of what looks like dark void energy that has a beam coming out from it. Those are the orbs I'm not sure about. The cores are Very small compared to these also.

@Saml565656 I'm not 100% sure but when I had one following me when I fought the Eidolon it took hate on some of the homing attacks. Also you can have multiple lures following you.

[Aekhon]

27 minutes ago, Saml565656 said:

What about those lures for the Vomvalysts, what do they do exactly? I found that they absorb three or four Vomalysts when they are in the bright blue ghost mode. The sort of get sucked in but then I cant don anything with the lures except have then follow me around. 

I don't know about combat wise, but if you don't want them following you, get close enough and you can tell them to stay put via interacting with them.

[Haif]

I noticed the fully charged lures firing some sort of blue beam into the shoulder.

Dunno what effect it actually has, though.

[NaughtyKat]

I have updated the post with a lot of new information gleaned during my second run, and a bit of a reformat. Please check it out!

@Saml565656 and @Aekhon, the Vomvalysts' role in the bossfight and abilities is one of the major things I don't yet understand. I think they have an ability to regenerate the Teralyst's shields if left unchecked but I am not sure. If anyone has more info on how they work, please post it for the benefit of us all!

[NaughtyKat]

@Haif I noticed blue lines as well, and I think I saw the Vomvalysts fire blue lines at the Teralyst as well. Still confused on how the Vomvalyst and Lure mechanics work.

[NaughtyKat]

@Althial did you kill all of the Teralyst Eidolon's phases? Or did you just beat the first phase (one round of shields and one round of weakspot shooting), making it retreat? And if you killed all of the phases, do you have more info on how the Vomvalysts and Lures work?

[Quedion]

I find using a Rhino/Prime is very useful to tank damage from the eidolon, using Guardian Dersion. Just make sure you get around 5,000 ferrite armor or it just wont hold up for long

[Guest MrCurlyFries275]

Operator beams will work on the small eidolon drones in normal form, tested 13th October

[Wikldash]

So haven't downed one but after 2 "nodes" are killed he starts to use a rocket pod which is a HUGE AoE Attack. (going into the Void lets you avoid all damage btw.) Also if a lure is attached to the Tera when one node dies it doesn't seem to teleport.

Edited October 13, 2017 by Wikldash

[bowdown2q]

 

1 hour ago, Guest MrCurlyFries275 said:

Operator beams will work on the small eidolon drones in normal form, tested 13th October

Operator powers damage the Vomvalysts in both forms, though in the first physical phase they seem to take less damage from them. [also 10/13]

4 hours ago, NaughtyKat said:

@Wikldash I'm not sure which orbs you mean, are you perhaps referring to the Sentient Cores? They look sort of like orbs, seem to drop from Vomvalysts in my experience, and you can trade them to the Quills for standing which you can in turn use to buy upgrades for your Amp and your Warrior Operator.

See that's what I thought too? It seems like it must be a bug; three of us picked up the same number of Vom' drops, but only *some* of those green-marked orbs registered as Cores, and at the end we all had different numbers. It seems like they're supposed to drop a core each? I just spent an hour killing about 30 of them and only have 7 cores to show :/ At that rate I'll see my first amp upgrade by christmas >>.

[VelarozDosun]

22 minutes ago, bowdown2q said:

 

Operator powers damage the Vomvalysts in both forms, though in the first physical phase they seem to take less damage from them. [also 10/13]

See that's what I thought too? It seems like it must be a bug; three of us picked up the same number of Vom' drops, but only *some* of those green-marked orbs registered as Cores, and at the end we all had different numbers. It seems like they're supposed to drop a core each? I just spent an hour killing about 30 of them and only have 7 cores to show :/ At that rate I'll see my first amp upgrade by christmas >>.

Those smaller orbs with the beams coming up from them are void energy drops, that refill your operator's energy--not in an immediate top off, but a quick regen buff. I think it only applies to the circle, rather than the beam.

[Harikusa]

About VOMVALYSTS

IMPORTANT! Those little guys in their glowing form do "rhino dash" thingy that deals loads of damage, probably equal to what Juggernaut does, probably more I was ash with 1k+ HP, almost oneshoated me.

It almost always drop so e resource that doesn't register as anything.

It seems they can make a clone, happed only once, it has the same HP but ofc doesn't drop stuff. 

Eidolon Lure drone

Can easily bugout if you have have couple of them, don't get more that 3, if you get too far they'll stup and agan, can bug out and stop listening to your comands. Sometimes in intenced battle they also listen awkwardla. Important bit, on your death they'll what? Yes! Stop following you!

[Sandhoof]

guide:

- take 4x slow nova

- take 4x shield disruption

- tigris prime + antimatter drop skill

 

speedkillrecord.

[Colonel-Corncob]

 

 Watch this! The guy in this video said that the lures seem to act as tethers.

[Milthar]

I've done a bit of playing and I can say that yes, the base operator void beam does deal damage to the eidolon shields, albeit a fair bit less. The vomvalysts can be killed by operators using an amp but forgot to test if the standard void beam damaged them or not.

After the Eidolons shield went down we were able to damage the knees of the Eidolon with both operator attacks and our regular warframe weaponry. After we destroyed one of the knee pads the Eidolon did a massive aoe magnetic attack which downed us all and then it disappeared.

woops looks like you already had that information, my bad

Edited October 13, 2017 by Milthar

[Ealonex]

A level 30 Basic amp does roughly 127-200 dmg to the eidolon's shield per tick. I'm not quite sure how much the base beam does.

@Milthar , you can avoid that via going to operator and staying in void mode (which lasts waaay longer now, I believe)

When facing against the Eidolon again after the second mag aoe, I find putting my warframe behind a hill with some aerial cover and then using primarily my operator to damage the Eidolon's shield fairly effective. The aerial cover helps if you die and get pushed back into your frame, but some random attacks (usually above and infront you) could insta kill you. Anyway, to avoid getting killed while in operator mode, I suggest alting between your void beam and your void mode. Use up all your beam, then void mode whenever the Eidolon does a high damage attack- Especially when he starts the meteor shower, as it's guranteed to kill you if you can't get far away enough.

Edited October 13, 2017 by Ealonex