Titan and MFK work great in a Shiva team due to their orb changing abilities. If you can manage to get a Freyr somehow, that 1.5x active skill will also be useful.
AKA what I have (Freyr). I was planning on using him, evolved, as a leader, but it's not necessary with Shiva.
All I need to fill that team is a Titan.
My layout is going to be
Shiva (Leader)
Freyr
Gigas
Echidna
Phoenix Knight
So 2 orb changers (heal -> Fire and water -> fire), Echidna aka the life saver, Freyr aka the "LET'S MAKE EVEN MORE DAMAGE!" and Shiva aka "Where's your defense?"
I can always swap Freyr or Echidna for a Kagutsuchi (although not ideal), red ripper (also not really ideal), another Shiva (for waay more damage and another -defense skill), Dino Rider (for wood -> fire and heal -> wood, although I don't really want wood), Flare Drall (for wood -> heal, which would work well with the Gigas)... So many different combinations to have fun with.
The last god fest was pretty kind to me (I did spend way too much money on it, though).
And one last thing: I don't mind farming tower of giants even when it's not 1/2 stamina, because I have nothing else to run today. Tomorrow it's jewel dragons + dragon plant day, so I'll have plenty to do, but I've got all the masks I need now for my next evolutions, the new tiers of dungeons are too hard to complete with any reliable accuracy, so I might as well focus on strengthening my teams...