Tethra's Doom

Tethra's Doom is an event released with Update 12.4. The Tenno must stop Councilor Vay Hek and the reforming Fomorian Fleet from dominating the system. The event began on Wednesday, March 5, and will end at 12 PM EDT on Wednesday, March 12.



"Tenno

We must move quickly. We have learned the nature of Project Tethra, Vay Hek is rebuilding the Fomorian Fleet. His aim is nothing less than complete domination of the Origin System. Thousands of these monstrous ships are in production. The Grineer will become unstoppable if they are completed. We must not let this happen.

Our goal is to cripple these ships before they can be deployed. To do this we are going to target the Fomorian Power Cores, their most vital component. This will be easier said than done. The cores are heavily guarded and their precise location is a tightly kept secret.

First we must find the cores. The Grineer are coordinating construction using a highly sophisticated encrypted communication system. To defeat this encryption, intercept multiple Data Fragments and combine them using the Tethra Cipher Blueprint I have sent you. When you have found a core, I will give you further instructions."

- The Lotus

What You'll Need To Do

 * You will receive reusable blueprints for the Tethra Cipher and the Tethra Shield Cipher from The Lotus. This will be your key to the new Grineer Shipyards.
 * Collect Tethra Data Fragments by playing the Tethra's Doom Interception mission on Earth. Two fragments are granted per successful mission, regardless of how long you stay.
 * The Tethra Cipher requires 3 Tethra Data Fragments, along with 1,000 Polymer Bundles, and 1 minute to craft (5 platinum rush build).
 * The Tethra Shield Cipher requires 6 Tethra Data Fragments, along with 1,000 Alloy Plates, and 1 minute to craft (5 platinum rush build).
 * Use your Cipher by either clicking the event operation in the screen after logging in, or through your keys menu, to access the Grineer Shipyards and Hijack the Fomorian Core.
 * In both Hijack Missions, you must find a Fomorian Core and activate the control panel to release it. Once released, the core will draw energy from your shields as it moves to the exit. The core will become unstable and its health will begin to degrade as it moves, with any damage it receives hastening its destruction. If the core runs out of health before it reaches its destination it will rupture, failing the mission.
 * In the Tethra Shield Hijack, the conditions are the same as before, but with stronger opponents. In addition, there are three locked gates on the way which players must hack to open, as well as mines placed on the track that can severely damage the core, so players must be vigilant.

Notes And Tips
General Tips
 * Here are some ways to counteract the shield drain of the cores.
 * Use a Warframe with high shields and/or high shield recharge rate, to withstand more damage while next to the core as enemies fire upon it. Guardian will also allow for quick shield recovery.
 * Using Mag's Shield Polarize can allow your team to indefinitely stay under core, quickening completion time, reducing core damage, and allowing for a higher score.
 * Alternatively, Trinity's Blessing can be used to replenish shields. The core will still sap shields through Blessing however.
 * Rhino's Iron Skin provides extra protection from enemies as the core only siphons shields.
 * Bombards or Napalms may spawn on higher ledges out of your view, causing a large amount of long range bombardments from these enemies. Counter this by using Loki's Radial Disarm with a build focused on maximum range.
 * Avoid setting off alarms as more enemies will further increase the difficulty of the mission.
 * Staying away from the core for too long will cause the Grineer to regain control of the tram and it will turn red and begin to travel back.
 * Nekros' Shadows Of The Dead and Nyx's Chaos can help draw fire away from the core, while Loki or Saryn can create decoys to divert the Grineer away from the Fomorian power core.
 * A Frost with a build focused on range can create a line of Snow Globes as the core moves along, protecting it enemy fire as well as slowing down any Grineer chasing after it.

Second Stage (Fomorian Shield Cores)

 * In contrast to the first stage you'll now need to hack consoles to open the doors in each room. Have someone go ahead to unlock any doors in your path. Warframes with mobility-boosting powers (such as Zephyr or Excalibur) are recommended for this task.

What You Should Know

 * Once you have successfully completed your mission, the Cipher will be consumed. To replay the Mission, craft a new Cipher using your Blueprint and the necessary resources.
 * As with all events, view your current highest score by clicking the bar on the top left of the main lobby screen.

Scoring
Upon completing each mission, you will be scored as follows:
 * Individual Scoring:
 * Power Core: The core health remaining is your score, divided by 10 (i.e. 5430 points of health remaining would equal 543 points).
 * Shield Core: Similarly, the remaining core health is divided by 10, then multiplied by 3 (i.e 2440 points of health remaining would equal 732 points).
 * Clan Scoring - Clan scores will be determined by the sum of each participant's best score. (How many participants?)

Rewards
'''Rewards will be handed out following the end of the event, at 12 PM EDT on Wednesday, March 12. You do NOT need to do the second stage to obtain the rewards from the first one.'''

First Stage (Fomorian Power Cores)
Individual Rewards
 * Tier 1: Complete mission with between 1 and 249 points and you will receive an Event Badge and a 3-Day Affinity Booster
 * Tier 2: Complete mission with between 250 and 499 points and you will receive the Tier 1 rewards plus the following four Mods:
 * “Jolt”: (Pistol) 15% Proc chance + 15% Electricity damage
 * “Shell Shock”: (Shotgun) 15% Proc chance + 15% Electricity damage
 * “High Voltage": (Rifle) 15% Proc chance + 15% Electricity damage
 * “Voltaic Strike”: (Melee) 15% Proc chance + 15% Electricity damage
 * Tier 3: Complete mission with 500 points or more and you will receive the Gorgon Wraith plus the Tier 1 and 2 rewards.

Clan Rewards

 * A Gold, Silver and Bronze Clan Statue will be distributed to the top three Clans in each Clan Tier.

Second Stage (Fomorian Shield Cores)
Individual Rewards
 * Complete mission with 1000 points or more and you will receive a Quantum Badge (a brand new type of badge that uses particles) as well as all three reward tiers from the first stage.

Trivia

 * According to Irish Mythology, Tethra is a Fomorian, strengthening this event's connections to Operation Sling-Stone. Tethra was also the name of a Fomorian ship stationed at Venus.
 * Frohd Bek briefly alluded to this event during Ties That Bind, as he pleads Darvo to stay with the Corpus.
 * This event was even foreshadowed after the Sling-Stone Event, as Alad V dispatched scouts to Pluto in response to rumors of surviving Fomorian-class ships.
 * Much like The Gradivus Dilemma, resource drops in the Grineer Shipyards currently use the Void's drop table (Alloy Plates, Gallium, Rubedo and Control Modules).
 * Towards the end of Livestream 24, the video feed was "intercepted" by Vay Hek to announce Stage 2 of the event. Amusingly enough, much of Hek's boasts reflected players' opinions of Stage 1 being "too easy".