Forerunners

The Forerunners were a foolsih race that did absolutely nothing to help anyone. In fact, they just made everything worse and blew a tiny squabble WAY out of proportion.

They built the Halo Rings, which were designed to destroy the Flood by killing EVERYONE. Who does that?

Not only that, once they'd killed EVERYONE and defeated the Flood, they decided to keep some alive and store them ON THE HALO RINGS. Thats like killing someone and then giving their son the gun you used to kill his dad and saying 'Now, be careful with that, my boy.'

They at least decided to preserve specimens of life forms and keep them safe on the Ark so they could be saved and reseeded back into the Galaxy...

They are similar in both appearance and fate to the Protheans. They were both races at their golden age millions of  years ago and were both wiped out in a mass extinction event. Except the stupid Forerunners did it to themselves, whereas the Protheans actually had an excuse.

Notable Forerunners

 * The Librarian
 * The Didact
 * The Janitor

Notable Forerunner Creations

 * Halo Rings (Installation 04)
 * Monitors
 * Guilty Guilty, aka 343 Guilty Spark
 * 2401 Penitent Tangent
 * 049 Abject Testament
 * 007 Greenie Spark
 * Sentinels