When I was first told of this: I thought someone was pulling my leg - BUT IT IS REAL and worth 143,000 Exp Points: you must be Level 50 AND it will not appear when you use the "Find Quest" button in your Quest box.
"Hidden Quest": Scarlet Gate
1. Speak to Elder of the Streams (130, 858) Thousand Stream City
2. Go to the Scarlet Altar (104, 513) THE QUEST WILL AUTO-TRIGGER THE CONTINUATION WHEN YOU GET CLOSE TO THE ACTUAL STONE. Must be standing STILL in order to get the quest continuation. (This is south of Sundown Town.)
3. Report to the Elder of the Streams (130, 858) Thousand Stream City -Collect 5 Bloody Jades (Farmable material. Located around [104, 513])
4. Report to the Elder of the Streams (130, 858) Thousand Stream City
5. Speak to the Etherblade Arena Manager (450, 879) Etherblade
6. Speak to the City of the Lost Arena Manager (245, 639) City of the Lost
7. Speak to City of the Plume Arena Manager (336, 432) City of the Plume
8. Speak to Archosaur Arena Manager (531, 630) South Archosaur
9. Report Elder of the Streams (130, 858) Thousand Stream City -Reward (Gold: 85200 Exp: 142000 SP: 32370)
Yes, it is a lot of flying, but well worth the effort (I personally, don't like to teleport unless really needed but this quest does pay you well, just fly up real high and auto-track while you do the dishes or...)