Any Heavy Cannibal (Big, Really Tall Guys With Bone Clubs) Can Kick You.
- I Have Only Seen Them Spawn In Cannibal Camps.
It Does Some Damage, But If You Put On Armor It Won't Hurt Too Bad, However Their Boneclub Swings Hurt A Lot.
This Achievement Is Cumulative For Your Current Playthrough, So You Don't Have To Get Kicked By The Same One 5 Times - Just Get Kicked 5 Total Times By Heavy Cannibals.
Good Luck!