What gods power Shazam and how did this change during Darkseid War?

On November 17th, 2015, /u/agnosgnosia – and, actually, a bunch of other people – asked the following on /r/DCcomics:

Who are the new gods that give [Shazam] his powers?

So, for those who may not know, during the current Darkseid War event – which, funnily enough, hasn’t had really that much Darkseid or even that much of a war – a bunch of the Justice League got new powers. Flash merged with the Black Racer, Batman is having a nice sit on Metron’s chair and, most importantly, Shazam – yes, the guy who used to be called Captain Marvel – got a whole new pantheon of Gods and a new title: the God of Gods!