Buy OSRS Jar of souls
The Jar of Souls is a rare drop from Cerberus in Old School RuneScape. Cerberus is a level 318 boss found in Cerberus' Lair inside Taverley Dungeon. The jar drops at a rate of 1 in 2,000, so it is a hard item to get. It is a members-only item and it is tradeable.
The main use for the Jar of Souls is in your player-owned house. You can use it on a boss lair display in your Achievement Gallery to show off a display of Cerberus. To build the display, you must have killed Cerberus at least once.
The jar also has some fun extras. If you use it on the Soul Altar in Arceuus, Sister Soul Jar will appear and do the Dance emote. If you use it on Adam, he will say he has been looking for souls and reach into the jar to take one.
The Jar of Souls is a great pick for collectors and house builders. It proves you have faced one of the toughest bosses in the game.