DISCLAIMER: I do not Own Mass Effect or Stargate. They all belong to their rightful owners.
The Krogan.
The krogan are a species of large reptilian bipeds native to the planet Tuchanka, a world known for its harsh environments, scarce resources, and overabundance of vicious predators. The krogan managed to not only survive on their unforgiving homeworld, but actually thrived in the extreme conditions. Unfortunately, as krogan society became more technologically advanced, so did their weaponry. The end result is that they destroyed their homeworld in a nuclear war that reduced their race into primitive warring tribes.
The Jaffa.
The Jaffa are an offshoot of humanity, genetically engineered by the Goa'uld. They have an abdominal pouch which serves to incubate larval Goa'uld. The infant Goa'uld provides strength, longevity, and good health, at the cost of supplanting the Jaffa's natural immune system, making them dependant on the Goa'uld for more symbiotes. The Jaffa have a warrior culture and form the armies of the Goa'uld.
Now these two Warrior Races will battle eachother. Will the Fast breeding warlike Krogan swarm and attack with Brute force, Or will the Jaffa turn the tides of the battle.
Who is the Winner.