The Index

The Index is a Corpus Arena-style mission type hosted by Nef Anyo on Neptune, in which Tenno and elite Corpus units fight to earn credits and other prizes.

Investment
Before entering the Index, the player initiating the mission must select an Investment amount in Credits that each squad member must pay in order to enter. There are three different investments:

Each player in the squad will be asked to invest the same amount of credits, and in public matches, players will be matched with others participating in the same investment tier.

This Investment will determine the Point Target the team has, which is a designated amount of Index points that the team must cumulatively deposit and score in the match. If the team achieves the Point Target during the match, their invested Credits will be returned and they will additionally receive the listed profit. The credit rewards are not split between players. Each player receives the full amount. However, if the team wins the match but doesn't achieve their Point Target, then their investment is only reimbursed without interest (need checking, but if the meta is not achieved, the investment is lost), and if the team loses the match then each player will lose their investment completely.

The credit rewards for winning is affected by credit boosters. Low risk is the most efficient in terms of profit returned vs points required.

Mechanics
The goal of the Index is to earn Index score for the team through the collection of Index Points, which are dropped by participants killed in battle. Represented as green, glowing diamonds, Index Points can be collected by walking over them, and then deposited to a designated bank location in order to earn the actual Index score. Every point deposited will add 10 more seconds to the timer, prolonging the match duration. When an enemy scores, the timer will go down by 10 seconds.

A player can hold multiple Index Points at once, and will gain bonus points for depositing large amounts at once, as seen in the table below. Bonus points will not affect the duration of the timer. However, holding large numbers of Index Points will apply the Financial Stress debuff which reduces the player's max health and shields, and constantly drain energy. All these effects are proportional to the number of Index Points held and are delivered through the Financial Stress debuff displayed by the player's HUD to the upper right.

Bonus points cap at +10 when reaching 20 points, therefore it's always recommended to deposit at 20, as there is no benefit in holding higher numbers of points.

The player's team will win if they score more Index Points than the opposing team before time runs out. If by the end of the match the players happen to tie, the tie goes to Nef Anyo.

If players meet the Point Target and are ahead of the opposing team, the game pauses and an extraction menu appears. Should players choose to continue, the Point Target resets and can be reached again to yield a bigger credit payout, otherwise they can leave with all their accumulated rewards. The wager is only subtracted at the start of the mission, and will not be subtracted again for choosing to continue. However, if players continue and lose the match, they will forfeit all rewards.

Specter Fill-Ins
The Index must be played with 4 players, however randomized Warframe Specters will assist the player and fill in unused spots on the team, such as a Mag or Frost, with a small assortment of weapons and even different color customizations. Their AI is similar to the advanced AI of the Investors, such as using abilities strategically and using parkour maneuvers. They will also try to protect the Specter or Player with the most points, following them loosely to try to give them some cover.

Warframe Specters will scale, however they can be more easily defeated than the player can in most cases, potentially giving Investors an easy way to obtain points.

Limitations
Energy and Health orbs are only available at preset dispenser locations throughout the arena, spawning periodically. Players are unable to use Companions and Sentinels during the match, and they are also unable to use Gear items.

The Brokers
Brokers are the elite Corpus units that participate in the Index to oppose the Tenno. These Brokers are divided into 4 different groups, with each group being selected at random as the opponents for a particular match.


 * -|Trading Group =

John Prodman
John Prodman is a legendary Corpus Prod Crewman that can be encountered in The Index after one hour has passed at any risk level. Known as Anyo Corp's "Employee of the Month", he drops an autographed poster when defeated, which can be placed in the Orbiter as a decoration once the mission is successfully completed.

Rewards
Aside from the bonus Credits earned from completing an Index match, at the end of match special Index Mods will be rewarded. Like the Executioner Mods introduced with Rathuum, these mods are special augments for certain weapons:

Operation rewards

 * 5 completed matches: The Index Badge, Access to The Index: Stage 2
 * 10 completed matches: Exilus Adapter, Access to The Index: Endurance
 * 100 total score in Endurance: The Index Sigil