[b]How do you open a vex portal? [/b][i] You have to stand on a vex sync plate.[/i] [b]So I have an idea/theory:[/b] [i]I think[/i] you have to go through a portal that hasn't been found/tried yet, and it will take you through the vex portal we see in the jumping puzzle to activate the chest, and once you go through it, the chest spawns in the tiny cave. So I think there is either a sync plate we haven't found yet(in the Gorgons lair), or it's in Atheon's lair. [b]This is my crackpot theory: I[/b] am wondering if during, or after, the last fight you can open the portal from Inside.... Like go into Venus, then run like mad to the Mars/Past sync plate and open mars from Venus/Future. Has anyone tried this? I know it would be hard due to going blind, and i don't even know if they will even work, but I thought it's worth a try. It's the only sync plates we don't use... [b]Go forth fellow Guardians! Explore the Vault! Search for a lone, long lost sync plate. [i]But Beware of the R.O.U.S.'s![/b][/i]