Foreword: As other people have mentioned, you can probably tweak this deck in many ways to give it a better winrate, such as replacing the Mirror Images. It doesn't make it a better Caiphennadin deck though, it makes it a better Skycrag deck. You could replace half the cards here to give it a better winrate, but it would no longer be the fun deck that it is currently. The purpose of the deck is to have fun making copies of Caiphus and Kenna. There are plenty of other options if you just want to win as often as possible.
My variation of Kaelos' list. It's surprisingly good, performing better in ranked than the old Kennadins ever did. Caiphus actually improves this deck by giving it a good unit to cheat out other than Kenna, and it synergizes as well or better with End of Hostilities. Basically you don't need to wait for the enemy to play good units anymore, you can just play your own.
The fun factor is through the roof with Caiphus. He can do up to 20 damage the turn he's played (charge, berserk, double damage) and frequently gets either charge or aegis (37% to get one or the other), which greatly improves the control matchup.
Grenadin Drone
x4
1
Permafrost
x4
1
Seek Power
x4
1
Torch
x4
2
Combustion Cell
x3
2
Spark Hatcher
x4
3
Assembly Line
x3
3
Ixtun Merchant
x4
3
Mirror Image
x4
3
Wisdom of the Elders
x4
6
Caiphus, Wandering King
x4
6
End of Hostilities
x4
7
Kenna, Shaman of the Scale
x4
Fire Sigil
x2
Primal Sigil
x3
Cobalt Waystone
x4
Crest of Fury
x4
Granite Waystone
x4
Seat of Fury
x4
Skycrag Banner
x4
View Deck on Shiftstoned
I don't think the deck would work with Jennev Merchant. This is a very expensive deck, make no mistake about it, and it's not the best one out there. It's really meant as a fun deck if you have extra shiftstone.