QFT

All this means is a mage , is trying to summoning a archdemon from hell.
Theres 5 g so it must be the archdemon who rules over the 5th layer of hell.

It begins wit a capital G. It must mean something...

Where's Dan Brown when you need him !?

Giant diplodocus feeds [on] sheep glands shooting diatrymas forwards, holding green shelves disintegrating for good horses salvation dinner [in] gratifying forest hay.

It all makes sense now!

Looks like someone was "debugging" the page's template and forgot to remove one of the "tests"... ;-)

all of my tests are strings of curse words, somehow I doubt that's a test so much as someone deliberately typing a clue.

After trying to break this code again. I have bad news.
The Darkspawn are being lead by a archdemon.This is a Blight!
by are number this has happen 4 times in past. That why theres 5 g.
To warn us of the 5th blight!

Well. A friend of mine who works as a software developer accidentally forgot to remove a, eh, "typical debug string" from a live production system.
It read: "Your mother" (In Norwegian). It was plain to see for all customers of said system who logged in for a couple of days until somebody in the company actually noticed it. Said system had a user database of, oh, about 100.000 at the time.

And that means, that the Age Of Darkness is coming! EA!
Oh wait, we've been there already... ;P /j

A coder probably fell asleep on the keyboard. Happens all the time - that and jelly donuts.

If that's a clue then this next game must be fucking annoying as to inspire someone to repeatedly headbutt the keyboard.

Oh so it must be Quake 2 then.

The decrypted phrase is actually "3"
As in, number 3.
Took NSA supercomputers weeks of cpu time.