#31 - Populous: The Beginning (Kudos to Player2 for guessing this)
As I've mentioned already multiple times in this thread, I love Bullfrog. I love them as much as it's possible to love any defunct developer. And yet, I had never played any Populous games before the third in the series appeared on the PS1; despite it being pretty much the series which put them on the radar.
While I realise it's nothing like earlier Populous and nothing like EA's attempts to revive Populous on the DS, "The Beginning" is an absolutely fantastic game and definitely the direction they should have taken the series had it survived longer.
Mixing God game with RTS in the most fantastic way, Populous 3 had you controlling the shaman of a mythical tribe who leads her people to conquer the galaxy. While controlling the shaman herself and having many supernatural powers at your disposal (something which was emulated in Lionhead's later "Black & White games"); you also had to manage a settlement of followers - build buildings for them; train them up as warriors or preachers and then ultimately go to war with opposing tribes.
I feel like Populous 3 was a game ahead of its time. You could terraform the landscape in fantastical ways which just didn't seem technically possible at the time. The combat was always a massive nightmare of attacks flying everywhere, yet it was fantastically fun to control.
And I've neglected to mention the best part of the game: the soundtrack. So soothing. You'll need it, to keep the stress of the actual game at bay.
Just like Dungeon Keeper, this one has gotten a recent spiritual successor in the form of Godus, something which I have yet to check out but keep meaning to.