The people of 1 Chronicles 12:8And of the Gadites there separated themselves unto David into the hold to the wilderness men of might, and men of war fit for the battle, that could handle shield and buckler, whose faces were like the faces of lions, and were as swift as the roes upon the mountains;
See All... with faces of lions. Who are they and did they have faces of lions?

Here is the verse in question:

1 Chronicles 12:8And of the Gadites there separated themselves unto David into the hold to the wilderness men of might, and men of war fit for the battle, that could handle shield and buckler, whose faces were like the faces of lions, and were as swift as the roes upon the mountains;
See All... And of the Gadites there separated themselves unto David into the hold to the wilderness men of might, and men of war fit for the battle, that could handle shield and buckler, whose faces were like the faces of lions, and were as swift as the roes upon the mountains;

The Gadites were the men of the Israelite tribe of Gad. Their territory was on the eastern side of the Jordan River in the highlands. They were known as a warrior tribe. This may be accounted at least partially to their rough life in the mountains of the east and to the fact that they were a border tribe that was separated from most of Israel by the Jordan River. They had to be ready to fight at a moment's notice.

This verse says that they had faces "like the faces of lions." They did not have the faces of lions. Rather, in some way their faces resembled that of lions. The use of the word "like" is very important. It points to similarity, not equal identity.

Lions are very distinguished animals in the Bible. They were known for their strength (Judges 14:18And the men of the city said unto him on the seventh day before the sun went down, What is sweeter than honey? And what is stronger than a lion? and he said unto them, If ye had not plowed with my heifer, ye had not found out my riddle.
See All...), their bravery (2 Samuel 17:10And he also that is valiant, whose heart is as the heart of a lion, shall utterly melt: for all Israel knoweth that thy father is a mighty man, and they which be with him are valiant men.
See All...), and their fierceness (Job 10:16For it increaseth. Thou huntest me as a fierce lion: and again thou shewest thyself marvellous upon me.
See All...). Many people in the Bible are compared in one way or another to lions. Judah is "a lion's whelp" (Genesis 49:9Judah is a lion's whelp: from the prey, my son, thou art gone up: he stooped down, he couched as a lion, and as an old lion; who shall rouse him up?
See All...). Israel shall "rise up as a great lion" (Numbers 23:24Behold, the people shall rise up as a great lion, and lift up himself as a young lion: he shall not lie down until he eat of the prey, and drink the blood of the slain.
See All...). Jonathan and David are said to be "stronger than lions" (2 Samuel 1:23Saul and Jonathan were lovely and pleasant in their lives, and in their death they were not divided: they were swifter than eagles, they were stronger than lions.
See All...). The list could be much longer. Benaiah, one of David's mighty men, killed "two lion-like men of Moab" (2 Samuel 23:20And Benaiah the son of Jehoiada, the son of a valiant man, of Kabzeel, who had done many acts, he slew two lionlike men of Moab: he went down also and slew a lion in the midst of a pit in time of snow:
See All...). This certainly refers to their strength and fierceness.

The Gadites are compared to lions in another passage. In the blessing of Moses on the different tribes, he blesses Gad with these words: "Blessed be he that enlargeth Gad: he dwelleth as a lion, and teareth the arm with the crown of the head"  (Deuteronomy 33:20And of Gad he said, Blessed be he that enlargeth Gad: he dwelleth as a lion, and teareth the arm with the crown of the head.
See All...). The tribe of Gad was compared to a lion.

So, what does the Bible mean when it refers to the Gadites as having faces like the faces of lions? It is describing the Gadites as having faces that were as fierce and bold as that of lions. They were not mutants, only fierce and strong examples of the human race.