Zurpstones growing on Sargasso.
Zurpstones are a collectible in Rift Apart specifically for the optional side mission "Help Trudi" on planet Sargasso in Rivet's dimension. They are large purple fruits that grow from the ground on the ends of plant stalks. They appear smaller and green when unripe. The fruits appear scattered around Sargasso's Outpost L51 and can grow in various locations, from caves to the top of high altitude cliff sides. Rivet can collect the Zurpstones either by hitting them with her hammer or with Trudi's fireball attack. There are sixty to be found in total.
Collecting ten Zurpstones will unlock the bronze trophy Feeding Friendsy.
The fruit is considered quite delicious and is used in cooking even on other planets. The drink Chef Tulio paired her meals with was a zurpified magma mead, a type of beverage made with Zurpstones. Also if Rivet completes the optional side mission for Tulio alone, she will think aloud to herself some of her favourite foods; one of which is flame-broiled sharkigator with a dash of zurp.
Trudi's stockpile of Zurpstones after Rivet has collected all sixty.
In "Help Tudi", Rivet is contacted by a Mort to return to planet Sargasso to help her Pterafoid Flyer friend, Trudi. Upon arriving, the Mort explains that she is simply hungry and usually flies to nearby rock islands to collect Zurpstones growing on them but is too weak to fly to get her food herself. Zurpstones are Trudi's favourite food and what she commonly eats, she also quite enjoys the fruit with Flurtian Spice sprinkled on them. The Goons-4-Less currently on the planet will frequently fight Rivet for the right to eat the fruit themselves to sate their own hungers and so they might use its protein in their strenuous muscle building diet. Wild Grunthors will eat them aswell and are also combated by the Goons-4-Less to get the fruit before it. Once Rivet finds fifteen, Trudi will eat them and be satiated but the Mort makes a deal to give Rivet rewards if she can find more. After collecting thirty zurpstones the Mort rewards Rivet with Ranger tactical pants and that she can ride on Trudi to fly around Sargasso quickly. After forty-five, Trudi obtains a fireball shooting ability for hitting the Zurpstones at the highest points of the map and with all sixty he will give Rivet a Spybot. With Trudi's large stockpile of Zurpstones, the Mort estimates it will take five days, six at the most for her to finish eating them all.