Gredella

Gredella is a gas giant of foreign origin due to its exotic composition as well as ring composition, this gas giant seems to have formed originally as a rogue world, containing dirty ice and other cold icy elements and rather few metals with a mass roughly 2.21 times the mass of Terrius(btw terrius is the same mass and size as earth) and 1
35 times its size making it a rather dense rogue world upon initial formation. This rogue world soon found itself in a foreign forming system, which was in the era of pre planetarh formation and it was just an accretion disk with a central young protostar, this world was on a slingshot around thks star, due to the abundance of gas and its time in the shstem, scientists think that due to the era that it ventured into the system may explain its large size (again its the abundance of gas) however it didn't stop there, after being slingshot, this new and now jovian ventured into a medium sized system in its outskirts, picking up a small ice world roughly the size of terrius and 0.921 its mass with its moon (now its moonmoon) due to a rogue world venturing in this world was slingshot out as this rogue world had a rather eccentric orbit, this gas giant then ended up into the Arago system where it currently resides, due to it being in the habitable zone, its ice moon is now an oceanic moon as well as its moonmoon