I followed puzzled's guide and kept track of everything I won. I revived Marion and Sandy, and had Alexandra do it before she died. So I have a total of 40 wins....wasn't easy, let me tell you!
1. Adon
---Carcharodon Wings (shield)
2. Alexandra (non-revived form, did her before she died so don't know if she gets anything different if revived)
---Nautilea Crown (helmet)
3. Angelina
---Vandorra (ring)
4. Ashkbar
---Inverness Bracers (shield)
5. Broff
---Gummi Chocolate (item) (+23 SP)
6. Brussian
---Silver Ivory Bracers (shield)
7. Cindy
---Mercantilus (ring)
8. Claria
---Tuula (helmet)
9. Cocka-Cocka
---Flavae Seed (item) (+25 HP)
10. Coryool
---Grand Shark Helmet (helmet)
11. Daryl
---Book-Inventing a New World
12. Deuterium
---Koraodeon Gear (helmet)
13. Djarma
---Cycca Diadema (helmet)
14. Fierce
---Xaurul (pendant)
15. Guanidia
---Kaba Nut (item) (+40 RS)
16. Herasia
---Book-Jungle of Hell
17. Herbert
---Valour Emblem (Pendant)
18. Joshua
---Book-Shrine of Yveen
19. Aaron (Kommender)
---Book-Comet of Overmohl
20. Kratin
---Palacia Shield (shield)
21. Leanda
---Doghma Circle (shield)
22. Leona
Didn't revive her, so don't know
23. Lily
---Double Trion (ring)
24. Louis
Cannot use him in Arena.
25. Luciana
---Book-St Christopher's Odysseus
26. Marion
---Book-Ten Centuries of Teaching (equippable, awesome!!)
27. Marylis
---Mermaid Glory (shield)
28. Nash
---Drukku Rose (item) (+33 MP)
29. Oglong
---Guano Truffle (item) (+31 ST)
30. Petula
---Nautilea Coral (item) (+26 MP)
31. Random
---Azuron (armor)
32. Rosa
---Mystery Drop (item) (+48 MN)
33. Sandy
---Book-Rise and Fall of Sarkham
34. Sarah
---Adretana Legendary Conch (item)
36. Tarabulla
---Iotezis (armor)
37. Timbany
---Camopeon (ring)
38. Vanina
---Saint Estella (helmet)
39. Wendala
---Kuka Slavarain (ring)
40. Xander
---Spirit of the Artifact (Shield)
41. Yveen
---Book-Grand Book of Glory
42. Kenny
---Book-History of the Saint Wars
After 36 wins, I was taken to the secret room. I think I got an Emerald Powder after each element flame fight.
In addition, when I finished all 40, I talked to Jendani and she says....Blah Blah Blah..."And if you ALL win... mystery!"
So I clicked through as she said each name and after all of them she said:
"... 39 wins...that's completely mad...I'll let you drink of this special Jouvence wine, don't tell anyone... I'm not supposed to do this, hihihi!"
And I received +999 HP (fill up) for each member of my party AND +100,000 EXP for each member. Plus, don't know if this is a bug or not (good bug if it is, very VERY good bug), but you can keep talking to her and keep getting that reward OVER and OVER again! You can change out party members and continue getting it.
I wrote everything down as I got each reward, but please correct me if I have anything wrong.