Yellow Eco is an Eco of power and specifically that of range, if channeled it can be used for long-range attacks. These attacks are similar to fireballs and will automatically seek out targets. It is also used to power long-range weapons. The sage of Yellow Eco is the Yellow Sage.
The Precursor LegacyEdit
In Jak and Daxter: The Precursor Legacy, Yellow Eco provided Jak with a fireball powerup. It was found in either balls, or in Eco Vents. Yellow Eco could first be found in the Boggy Swamp, and was complusary in the mission Protect Farthy's snacks, and appeared in the final battle against Gol and Maia's Precursor Robot.
Jak II & 3Edit
In Jak II and Jak 3, Yellow Eco only appeared in the Yellow Mod of the Morph Gun. It was no longer found in Vents, or as floating balls of Eco around the world, for reasons unknown, but presumably relating to the concept that the world was 'running out of Eco'; in the games, Eco seemed far more absent than in The Precursor Legacy. The Yellow Mod was acquired from Krew in Jak II, and from Damas near the beginning of Jak 3.
Jak X: Combat RacingEdit
During Jak X: Combat Racing, Yellow Eco was found in racing matches only. It was used as racing powerups to activate offensive weapons in the vehicle. Yellow Eco powerups appeared as two floating pyramids with the bottoms hold together by a metal square. It can be assumed that the Yellow Eco was put together in powerups by Mizo when arranging the racing.
The Lost FrontierEdit
In Jak and Daxter: The Lost Frontier, Yellow Eco was found once again in Yellow Eco Vents. It was used in Eco Powers and Skills. It was used in the power Eco Rocket Jump to extend Jak to new jump heights, and one of the Eco Skills allowed Jak to shoot fireballs with Yellow Eco again, but this time was a passive ability. However, it was still used in the Gunstaff, the Morph Gun's replacement.
In The Precursor Legacy, Jak could channel larger clouds of Yellow Eco, or vents of Eco, and shoot fireballs. These fireballs were fairly slow moving, and would automatically target enemies. They could also break open metal crates, which were otherwise unbreakable without Flut Fluts. Yellow Eco would kill Lurkers in one hit, as well as break armor.
Yellow Eco was in the Yellow Mod, a mod for the Morph Gun and Gunstaff. It would provide ranged weapons, such as the Blaster, Beam Reflexor and the Gyro Burster. These weapons could target enemies well, and reach a long range, but was not so useful when against larger groups and in close combat.
When used in racing, Yellow Eco powerups were used to provide the vehicle with an offensive weapon. These include weapons such as the Peace Maker, the Vulcan Fury and the Tracking Missiles, as well as the Submachine gun. They can be used to destroy the opposition's vehicles, or at least damage them, to help reach the front. Yellow Eco weapons could be upgraded with Dark Eco to become more powerful. Technobliterator: That's for Yellow Eco
Eco Powers & SkillsEdit
Yellow Eco provided the Eco Power Eco Rocket Jump, which allowed Jak to jump higher than usual, as well as to glide, while Jak had enough Yellow Eco to power it. Jak could also acquire Eco Skills for Yellow Eco, which included upgrades to the Rocket Jump power, as well as Yellow powers added to Jak's melee lineup, which included a fireball power added to Jak's punch, like in The Precursor Legacy.