You decided to just kill everyone in a day. You walked into town and got some looks, made sense as the town was isolated by a bunch of undead and some dark magic type thing comes walking into town and what else would you do? A single attack on the person could mean you just doomed your town to an invasion, but you wouldn't be that welcoming either. You looked around and saw that it was a rather lively town with a couple of stranded travelers trying to make a living in the streets. However none of them were that magically inclined and were either simply proficient with weapons or was a merchant or crafter. Well no one would really be able to oppose you in town which was nice. You felt someone tap your shoulder and looked behind you and saw a fairly well dressed man with a neatly trimmed beard.
The man said "Why welcome to this town... Sir?... May I ask how you've managed to get through the undead horde?"
You projected your thoughts into the man's mind "Have you kept track of everyone in town?"
The man a bit uneasy said "Well... Yes just to make sure we can survive and maintain some sort of order in here. Ration out supplies accordingly. I mean if we didn't then we'd have starved long ago."
projecting your thoughts to him you said "My father gave me a mission involving this town."
The man a bit scared asked "Uh is this a sort of peaceful mission?"
your thoughts went from just the man to everyone in the town area into "Well I hope this is adequate to say what sort of mission it is." as you raised your hand and a dark mist enshrouded the man who started gasping for breath and then stopped. You sensed his soul trying to leave but you pinched your thumb and index finger of your right hand and trapped the soul into the man's body which was becoming more visible. The man's skin looked purple and his eyes were bloodshot and rolled up in his head. You then raised your right hand up and the man's body raised and his eyes stared at you.
There was a lot of screams as the man then stared at his hands which opened and closed as words escaped his mouth "I'm alive and can think?"
Your thoughts went out to everyone in the town area and said "Well you can think for yourself, but there is no life in your body." you broadcast your thoughts out to everyone in the town "Here me everyone! I am the son of the Warlock who has you all entrapped here, and as a birthday present he's asked that I end all life in this town within a week. If I don't then likely my own life is forfeit and your lives will all definitively end for good. However I don't have that much interest in just outright ending your existences in our glorious world. So i'll make this simple. Do not hide from my magic that will end your lives. If you don't then my reanimation magic will reach you in time and you'll still have your free will. Hide and my reanimation magic may not find you and you'll just stay dead. Your choice, but remember that being undead is a whole lot better than being actually dead."
You then focused on casting a spell as a dark mist started being generated around you as it spread through the town entering the cracks and pores of the wooden buildings and you could tell most everyone had started to die. You ended the casting as the mist would flow through the entire town killing everything alive. Then you started casting a second wave of magic meant to bring back everyone. It wasn't a mist that would seep into every nook and cranny so those who weren't in the open or in a fairly open room in a building wouldn't be brought back as undead but those people had a good couple of seconds to get out into the open. After the second spell finished casting you dropped to the floor gasping as you were almost out of the dark energy that you used for magic and life. You shouted out "Hey some undead bring me some food! If I go down the rest of you go down as well!" Some random undead guy brought you a simple loaf of bread which you took and said "Thanks Sir." and then started eating the bread.
The guy said "So what now?"
You said "Wait a week. Dad will then come buy and inspect everything and make sure the jobs been properly done. May have a little fun with some experimentation in the mean time but nothing without willing volunteers. However what to do now... i've got a little magic but... what to do?"