Once You Make An Archer's Hut You Can Fight These Guys.
- Building A Watchtower Means You Won't Have To Run Away From Them After You Aggro Them.
- Skeletons Are Inactive And Invulnerable During The Day.
Without A Watchtower Use Two Villagers, One To Shoot, One To Lure It Away.
Achievement Pops After It Dies.
Good Luck!