siphi is among the best champions in the game, so i certainly wouldn't call you unlucky. short term, you can probably leave one in the vault, but eventually you could have one built for arena and another for dungeosn/cb if you wanted. alternatively, you could use one as a tome for the other (wouldn't recommend) or hold onto the second one in the hopes that plarium will drop the duplicate system they've been mentioning for ages without any concrete details.

thanks aloy

use each in each tag team Arena. 

thanks for the idea

Use both in normal arena, with Valk and Tormin. Your enemies will just quit out of frustration.

Put  both of  them  in  a  Bronze  1  arena  defence  with  Tormin  and  Valkyrie  and  see  how  many  screenshots  of  them  you  can  get  posted  to  this  forum.

2 siphis in an arena defense can deter many a player and also be a apain to deal with provided they're fast and tanky enough ( or better yet in swift parry uhg ! ) 

each can be a part of a different 3v3 team again doing a great job in each 

Doom tower will be much easier

Needless to say faction wars and most of doom tower will also be a breeze. 

They can theoritically help you overcome any hard roadblock in the game (with a few exceptions ) 

That said as advised before it would be wiser to focus on developinga  core team of level 60 first while keeping that second siphi at 50 for a while she'll still be alot of help 

according to the champions i have

who should be the core? 

Valk Tormin Siphi and?

nah, the only problem is Tormin. 1 or 10 Siphi would not be a problem with Serris. I have Serris. 

And Maneater still at lvl1. LOL

There are a few champs let me hesitate when attack, Siphi is not in the list.

- Champs with speed aura 30% (or more if any). Since the game is speed rule, not sure if I am faster or he is.

- Tormin (or similar): to those haven't got him he is a cancer, when unluck, my champs would be frozen all the time. 

- Hegemon: this guy is also a cancer for those haven't got him, he always go first and cast [Block Cooldown], the fight end. 

Just out of curiosity. How long have you been playing and how much money did you spend on the game. I see a High Khatun so probably 30 days or more but then I see 5 legendaries and quite a lot epics wich would indicate several months. Unless you spend like a shitload of money. And Iam torn since you dont have a decent level 60 and your gear is shit :D

Personally I would just try to get all those legendaries to 60 first. That would be my main goal. And ascend them ofc.