The attacks we've suffered so far have cost us many lives but left us with valuable lessons. The shambling creatures the science teams are calling 'Necromorphs' appear to be made of the dead remains of other creatures, including our fallen soldiers.
This is disturbing, disorienting and shocking on first site. Steel yourselves, as it may be a psychological ploy of the creatures to weaken us.
Critically important: Shoot for the limbs! They otherwise keep coming and will behead you before you can reload. Body and head shots essentially waste ammunition, so you must quickly retrain your basic marksmanship.
Never allow a breach of the outer wall! A single creature can take out an entire wing and begin a replication process within minutes.