Get Seals 1, 2, 3, and 4 and talk to the NPC in Yuno.
You have to pass the SQI arena with 6 people by fighting 10 MVPs in a maximum time limit of 10 minutes. The MVPs are Tao Gunka, Turtle General, Evil Snake Lord, Baphomet, Mistress, Doppelganger, Dark Lord, Stormy Knight, and two very strong Baphomet Jr. from Hell (so if you don't have a party of 6 people able to beat all those MVPs in 10 minutes, stop reading this post).
For those who have passed the arena: the SQIs are hard to make; it's not something you can do in one week.
After passing the arena you access Valhalla again without passing the arena another time.
Here is where you can get the seal:
SEAL-1
The first of four tickets required for one player to access the Super Quest Item arena.
Dropped By : Bacsojin, Dark Lord, Evil Snake Lord, Stormy Knight, Tao Gunka
SEAL-2
The second of four tickets required for one player to access the Super Quest Item arena.
Dropped By :Baphomet, Doppelganger, Orc Lord, Incantation Samurai, Turtle General
SEAL-3
The third of four tickets required for one player to access the Super Quest Item arena.
Dropped By : Drake, Lord of Death, Osiris, Maya, RSX 0806
SEAL-4
The last of four tickets required for one player to access the Super Quest Item arena.
Dropped By :Amon Ra, Eddga, Dracula, Garm, Golden Thief Bug, Mistress, Moonlight Flower, Orc Hero, Pharaoh, Phreeoni
