I know that the Romans were very organized in battle, but in the thick of fighting each other, how could they tell friend from foe? Did they alter their uniforms?
Not to discourage any further answers, but you may find these older answers to be interesting.
How did soldiers tell friend from foe during open battle in ancient Roman civil war? by /u/HatMaster12 and /u/Iguana_on_a_stick
And
During Caesar's Civil War, when the battles were fought, how did the Romans know who was who? by /u/Celebreth