I have to disagree with some of the comments in this thread. Whilst I didn't much like the look of him, Pharos-Ra is a great troop.
I also use him at the bottom of a team with Gorgotha, Giant Spider and The Dragon Soul above. I use kraken banner strangely enough, just to give me the option of starting off by filling either Gorgotha or Giant Spider. Frozen banner would also be a good choice.
Pharos is the best sniper troop that I've used. I would be gutted if they change his spell to stop the yellow>purple conversion.
One thing people may not realise is that casting him once when you have zero souls nets you 50 souls due to his +150% souls trait. So if he's full and you have the opportunity to use him and get a second turn, you use him once for 19 damage and then a second time for 69 damage (maybe using giant spider in between to top up his mana). If you've cast TDS once already then the first hit is already 56 as TDS gives 37 souls! So after two casts you have 100 souls and Pharos is doing 119 damage per cast.
Using exploders means that the board is regularly reset to give a higher chance of a second turn from Pharos's spell. Also, you can often use the spider to create the required board to get an extra turn.
NB: these numbers are with deathknight armour, max guild statues and max kingdom magic bonuses.
IMO he is well worth the cost of traiting and he does feel like a mythic powered troop.