First introduced in Update 24, the Fortuna update, this resource may be difficult to find at first. It only appears on one map. Fortunately, once the player knows where and how to look, it is easy to find it. Just like the fish oil in The Plains of Eidolon, players can only find thermal sludge in the Venus’ snow-covered free-roam area, Orb Vallis.
Unlike fish oil, players do not need to play special fishing mini-game to find it. Obtaining thermal sludge is a much simpler task, similar to finding common resources on a smaller mission map.
In Warframe, thermal sludge is a by-product of Corpus using the Orokin Terraforming Towers. This is an important clue about where to look. The corpus stores thermal sludge near their outposts, labeled “thermal sludge canisters.” Most of the named areas on the Orb Vallis map will have The Pearl, Temple Fabrication, and The Spaceport.
Players can also get thermal sludge as a reward for bounties. Compared with direct search, this method is much slower. After all, thermal sludge is only one item in the potential reward pool. But for players seeking rewards for other reasons, this is a great bonus.