After seeing you write that the controls for the game are in the game description, I realised how to play. I think it's generally best practice to include the controls/tutorial in the game itself, just so that the game can be fully understood by itself. Especially because some important controls, mainly right arrow for repairing buildings, are not really intuitively bound to buttons on the keyboard.
The faith-mechanic is really interesting! It replaced 'mana' or 'energy' as something that actually fits really well in the internal logic of the game, that was smart! Doing attacks with the mouse was fun as well, and their variety gives the gameplay a fun depth. I'm not sure if the lightning attack actually functions well, I couldn't get it to connect.
Visually you've got a nice consistent style, I liked the chest-thumping the vikings do when attacking, that was funny. Information on the HUD wasn't properly displayed on my screen though, I could only clearly see the faith currency.