Research

An Empire can greatly strengthen all aspects of itself through Research. Most technologies can be unlocked by spending Science, but other, hidden technologies are unlocked by completing Faction or Side Quests. Each technology that is researched unlocks one or more city improvements, a military unit, a special ability, or a passive benefit for your Faction.

The Research Tree is divided into six distinct tiers or "Eras". At the beginning of a game, only Era I is available; other Eras must be unlocked by researching nine technologies from any previous Era. The only prerequisite to research a technology is that the era in which it is located has been reached. Once an Era has been reached, any technology from that Era is available for research. All Major Factions start out with two technologies already researched.

To research further technologies, you must go to the Technology Tab and select a technology to research by left clicking it. Only one technology can be researched at a time. Selecting more than one technology will queue additional technologies, in the order in which they were selected. To deselect a technology, or remove it from the queue, simply left click it again. Every turn, your faction's total Science output is applied toward the technology at the top of the queue. If your faction has a higher Science output than what remains on the selected technology, the surplus will be applied to the next technology. If research on a given technology is stopped in favor of another, the progress towards the first technology remains and the technology can be resumed at any point. Note, however, that this progress is percentage-based, so returning to a technology after researching a few others will result in it costing more to finish than it had before.

Technologies do not have a set Science cost. Instead, all technologies have a cost based on the era of the technology and the total number of technologies researched. With N being the number of technologies already researched, and A being a constant based on the technology's era, the equation for the Science cost of the next technology is:

Cost = A * (5 - N + (N + 1) ^ 2)

The value of A for each era is as follows:

There are a number of effects that become active upon reaching a new Era, such as units being trained at a higher level, new equipment being unlocked, and certain tiles and resources being revealed. Additionally, whenever any empire in the game reaches a new Era, all of the Legendary Deeds for that Era become available for everyone to complete, and all facilities for that Era are revealed.

Era I
This is the Age of Discovery.

Unit Technologies
Each faction has a unique unit that is available to unlock through research in Era I. The Necrophages' Necrodrone and the Allayi's Skyfin are unlocked by default.

Era II
This is the Age of Glory. Upon reaching this Era, the following effects come into place:
 * Iron tier 2 weapons and armor become available for heroes and ground units
 * Newly trained units will now be veterans (level 2) and cost more
 * Watchtower foundations are revealed
 * Empire plan level 2 available

Unit Technologies
Each faction has a unique unit that is available to unlock through research in Era II.

Era III
This is the Age of Enlightenment. Upon reaching this Era, the following effects come into place:
 * Iron tier 3 weapons and armor become available for heroes and ground units
 * Newly trained units will now be masters (level 3) and cost more
 * Luxury Resources revealed: Blood Crystal, Grassilk , Moonleaf , Quicksilver , and Titan Bones
 * Strategic Resources revealed: Adamantian and Palladian
 * Empire plan level 3 available

Era IV
This is the Age of Industry. Upon reaching this Era, the following effects come into place:
 * Dust tier 1 weapons and armor become available for heroes and ground units
 * Newly trained units will now be elites (level 4) and cost more
 * Luxury Resources revealed: Dust Orchid, Dustwater , Hydromiel , Pixie Blood , and Redsang
 * Strategic Resources revealed: Mithrite and Hyperium
 * Empire plan level 4 available

Era V
This is the Age of Heroes. Upon reaching this Era, the following effects come into place:
 * Dust tier 2 weapons and armor become available for heroes and ground units
 * Newly trained units will now be elites (level 5) and cost more

Era VI
This is the End Of Ages. Upon reaching this Era, the following effects come into place:
 * Dust tier 3 weapons and armor become available for heroes and ground units
 * Newly trained units will now be elites (level 6) and cost more