Eco is a mysterious elemental substance with various powers and purposes, both known and unknown. Originally created by the precursors, it was studied by sages and later used in various technologies in the Haven-era timeline. Eco is produced at the Eco Core and is considered a vital element in the universe.
The Precursor LegacyEdit
In Jak and Daxter: The Precursor Legacy, Eco was most prominent. Eco was found mostly as floating particles, and when acquired, would provide Jak with temporarily augmented abilities. Eco could also be found in Eco Vents. Dark Eco, however, would merely hurt Jak if he so much as touched. Dark Eco was found in Dark Eco Boxes and in Dark Eco Pools. Light Eco only appeared in the last level, where it is used similarly to Yellow Eco during a cutscene.
Jak II & Jak 3Edit
In Jak II and Jak 3, Eco was less plentiful than in The Precursor Legacy. Eco seemed to be used as Haven City's main power source, as it was used for the Morph Gun's ammunition, as well as the Eco Grid. Dark Eco became much more plentiful in these games, virtually replacing all the original forms of Eco for temporary abilities.
Jak X: Combat RacingEdit
All the Ecos were featured in Jak X: Combat Racing, with the exception of Light Eco. All Ecos could be found as powerup along the tracks, each Eco providing a different power up, with the exception of Dark Eco, which was acquired by destroying enemy vehicles.
The Lost FrontierEdit
In the latest installment, Jak and Daxter: The Lost Frontier it is stated that the world is "running out of Eco", hinting that the world is at a very old age. This could also be because the precursors left to fix what the dark makers had done to their many worlds so the Precursors couldn't be there to make it. This may explain the disappearances of Yellow, Red, and Blue Eco in Jak II and Jak 3, as well as Baron Praxis's decision to turn to Dark Eco as a means of fighting, rather than the less harmful forms of eco.
Green Eco contains the power of healing and growing things, and is used throughout the series as a means of restoring health – one section of the heart meter in Jak and Daxter: The Precursor Legacy, two sections of the health meter in Jak II and Jak 3, and more than half of the meter in Jak X: Combat Racing.
In Jak and Daxter: The Precursor Legacy, Green Eco appears as small floating particles in groups of three or four, or as a large cloud equal to fifty of the smaller particles. Both the small particles and the larger clouds can be found in boxes, or by defeating enemies. On Sentinel Beach, Green Eco can also be found in vents; stepping into one of them fills Jak's heart meter to maximum capacity.
In both Jak II and Jak 3, the main source of Green Eco is the Krimzon Guard Health Packs. There are, however, several Green Eco vents found in Southern Haven Forest during Jak 3, albeit only in one mission, and not primarily for restoring health, but to kill Dark Eco-infected plants.
In Jak X: Combat Racing, Green Eco is scattered throughout the tracks and is used to repair your vehicle.
Blue Eco contains the energy of motion; in Jak and Daxter: The Precursor Legacy, it is used to increase Jak's speed, attract Precursor Orbs, break boxes and attract their contents, and to activate many Precursor artifacts. After Green Eco, it is the most widely spread kind of Eco, with vents and clusters appearing in almost every area. As befitting its ability to increase speed and power machines, Blue Eco resembles blue lightning.
In Jak II and Jak 3, the Blue Mod(s) of the Morph Gun resemble the Characteristics of Blue Eco (as all the Mods do), fast, precise; lightning like.
In Jak X, it is found as a capsule-like object on the tracks and used as turbo.
Red Eco increases the user's strength, making it possible to slay more powerful enemies in a single blow. Jak's jump-dive attack is also enhanced while he is using Red Eco - a small shock-wave of Red Eco will destroy any enemy within range. However, there is a slight drawback in the fact that use of Red Eco makes the user slightly slower. On Misty Island, as well as a few other places, clusters of Red Eco can be found in boxes, or by destroying certain enemies during the Lurker ambush; it can also be found in vents on Snowy Mountain. Red Eco clusters are thick, and resembles fire when coming from vents.
The Red Mod(s) in Jak II and Jak 3 are the same in their characteristics; slow, powerful, and better at close range. In Jak X, red eco appears as a glowing red capsule on the track, and is used as defensive weapons to avoid missiles or to hinder/kill opponents behind you.
Yellow Eco, a more long-range offensive weapon than Red Eco, allows Jak to shoot fireballs from his palms that home in on enemies. As well as its usefulness at destroying enemies from a distance, Yellow Eco is also useful for destroying obstacles such as Dark Eco boxes and opening strong boxes. It is particularly abundant in Boggy Swamp, though vents are also found in the Spider Cave, on Snowy Mountain and in the Lava Tube. It resembles an amorphous cloud of gas.
The Yellow Mod(s) in Jak II and Jak 3 are similar in Characteristics as well; Long Range, Average Power, Average Speed; a great all 'rounder.
In Jak X, yellow eco appears as a glowing yellow octahedron along the tracks, and is used as offensive weapons to kill the opponents in front of you.
With its ability to warp and mutate, Dark Eco is considered the most dangerous kind of Eco. Large amounts resemble a thick black ooze with a purple sheen; smaller amounts, as dropped by enemies in Jak II and Jak 3, are seen as shifting purple spheres.
During Jak and Daxter: The Precursor Legacy, Dark Eco was seen in containers, deep underground pools, or in Precursor Dark Eco Silos, as well as in solid crystalline form. In Jak 3, Dark Eco was also shown in crystal form, in vents at the Monk Temple and in the Ruined Stadium. Daxter's famous transformation into an Ottsel was caused by falling into a pool of Dark Eco on Misty Island during Jak and Daxter: The Precursor Legacy.
In Jak and Daxter: The Precursor Legacy, they do harm to Jak. In Jak II or Jak 3, however, they serve to augment Jak's abilities, replacing all other types of eco except Green Eco. However, large amounts of Dark Eco are still harmful to Jak. The Dark Mod for Jak's Morph Gun is extremely powerful, but drains the ammo of the weapon greatly. In Jak X, when Jak continues to get fired upon or kill opponents, dark eco upgrades his weapons and fully restores his health.
The rarest of all Eco in the world, Light Eco can occur naturally in vents in Jak 3, or can be created artificially by combining Green, Blue, Red, and Yellow Eco. In Jak 3, some enemies will dissolve into small spheres of it when defeated; it also appears in vents inside the mysterious Monk Temple, The Ruined Stadium, in Spargus City near the coast, and in crystals.
In Jak 3, Light Eco enables Jak to transform into Light Jak, allowing Jak to heal his wounds, slow time, create a protective shield around him, or channel it into artificial wings used for reaching high places.
In The Precursor Legacy, Daxter theorizes, presumably correctly, that Light Eco may be the key to reversing his transformation. In Jak 3, this claim is supported some because the Light Eco can be used to balance Jak's imbuement of Dark Eco.