God is all-good and therefore doesn't "slaughter" anyone.
...do not leave alive anything that breaths. Completely destroy them...as the Lord your God has commanded you...
Deuteronomy 20:16
And it came to pass, that at midnight the LORD smote all the firstborn in the land of Egypt, from the firstborn of Pharaoh that sat on his throne unto the firstborn of the captive that
was in the dungeon; and all the firstborn of cattle.
Exodus 12:29
21 All flesh that moved on the earth perished, birds and cattle and beasts and every swarming thing that swarms upon the earth, and all mankind;
22 of all that was on the dry land, all in whose nostrils was the breath of the spirit of life, died.
23 Thus He blotted out every living thing that was upon the face of the land, from man to animals to creeping things and to birds of the sky, and they were blotted out from the earth; and only Noah was left, together with those that were with him in the ark.
Genesis 7:21-23
Yahweh confused them before Israel, and he killed them with a great slaughter at Gibeon, and chased them by the way of the ascent of Beth Horon, and struck them to Azekah and to Makkedah. It happened, as they fled from before Israel, while they were at the descent of Beth Horon, that Yahweh cast down great stones from the sky on them to Azekah, and they died. There were more who died from the hailstones than who the children of Israel killed with the sword.
Joshua 10:11-11
23 And he went up from thence unto Bethel: and as he was going up by the way, there came forth little children out of the city, and mocked him, and said unto him, Go up, thou bald head; go up, thou bald head. 24 And he turned back, and looked on them, and cursed them in the name of the LORD. And there came forth two she bears out of the wood, and tare forty and two children of them.
2 Kings 2:23-24