Who killed Markiplier?

Let the investigation begin,

                                                      The body was Mark's, his cravat missing and his silk roble disheveled and ripped in some places. He wasn't breathing. Was he dead? How? And who could have done this? And why? Before you could ask anyone for the answer to these questions, the man from earlier who was talking to Damien walked into the room. He was wearing a white bathrobe and deerstalker hat, "Did anyone hear that lightning? Oh my God! There's been a murder!" Lightning flashed as he yelled the words. He looked down at Mark's unmoving body. Another voice was heard, "Excuse me, did you hear the light-Oh my God murder!" It was the Butler, and more lighting came when he spoke as well. He rushed passed you to the body of your now dead friend. One more voice cried, "Did you-? Murder!" Lighting sparked again at the mention of murder. It was the Chef, who was now pointing to Mark's corpse. The man in bathrobe suddenly grabbed your shoulder, "What the hell happened here?!" He cried shaking you. "Who's in charge around here? Trick question! That guy!" He pointed to the unmoving Mark, while the Butler checked for life sighs. "And he's dead now which makes me in charge. So you better listen up good bucko. Case you haven't been paying attention there's been of a... killin'." The man at squinted at the sky, looking for signs of the mysterious lighting. None showed up, "And you're my prime suspect, so you better get to explain' right quick as to the what, where, when and why you happen to be here upon this man's death!" He started, but the Butler interrupted. "Sir, the body's cold. He's been dead a while." He spoke, standing up. The man laughed, "A likely story! That I happen to believe completely. Alright, you're off the hook, for now, but I'm a detective and-" He started to say to you. But the Chef jabbed a finger at him, "Oh yeah?! Prove you're a real dick!" The Detective reached into the pockets of his bathrobe. Pulling out what looked like a wallet. "Here's my badge, asshole." He sassed. As the Detective turned to you, some pictures fell out like an accordion. The Detective began to fold the pictures up, "Ah, those were my old partners. Don't ask me about them," He paused, but then spoke quickly, "Fine! I'll tell you! Each one of them died, each death more tragic than the last, a few of them even died in ironically hilarious ways." He added. You looked to the Chef for some kind of reassurance. But got none, "Which made it all the more tragic, but hey, you look like you're up to the task. You're my new partner!" The Detective smiled with a bilious expression. You shook your head wildly no. If all of his old partners die, and there's a murder in the house. What's to stop the Detective's curse from coming true? A laugh interrupted your chain of thought, "That's what all my old partners used to say. Right before they died..." The Detective trailed off, you looked at the Chef again. And he looked just as concerned as you felt, "Huh... Anyway, had me that fingerprinting kit behind ya, partner." The Detective winked. You whipped behind you to see an emerald green velvet couch, there was no kit. As you turned back to the others to tell them this, the Detective tossed a black bag on the ground. How did he get that? "Thanks partner." The Detective's look changed, he no longer wrote a snow white bathrobe. But a patterned necktie, sky blue dress shirt, tweed vest, dress shoes and pants. A trench coat replaced the bathrobe, he bent down to see under the cotton sheet that covered Mark's body. Apparently the Butler and Detective had setup a crime scene investigation while your back was turned. How did they do that? You bent down under the bright yellow caution tape that was wrapped around the carved walnut fireplace. And other areas of the room where you had spent the majority of last night. You stood back up, the floor creaking from the weight of 3 people and a dead body. Footsteps from someone wearing dress shoes tapped into the room. You looked to see that it was Damien, who then spoke, "What the hell happened here?" The Butler turned to answer, "Oh, Mr. Mayor, I'm so sorry there's been a murder." Thunderclaped at the word. "A murder? But who?" More lighting and thunder answered the Mayor's question. The Chef shrugged, "It's Mark." Damien looked taken back, but before he could say anything the Detective rose from looking at our dear friend Mark. "I'm afraid he's telling the truth. Mark's been...Killed." The Chef looked up, no signs of lighting. "But why? Who would do this?" Damien asked again, he sounded so heartbroken. Mark was his childhood friend, and had known him much longer than you have. "That's exactly what me and my new partner are here to find out." The Detective motioned to you, you gave Damien a reassuring look. You were going to find who killed Markiplier, even if it was a little dangerous. "Um, excuse me, I feel like we should call the authorities for them to handle this matter." The Butler spoke solemnly, the Detective turned to him and sighed. "Look buddy, as far as your concerned, I am the authorities." The Detective pulled out his badge again, the waterfall of photos of his old partners fell out once more. "The fact of the matter is I believe the killer is right here amongst us in this very house. With that freaky lighting storm outside, none of us would get very far anyway." The Detective started to put away the photos but got caught on his words, and eventually just shoved the badge in his coat pocket. "So, in the meantime, we're stuck here." He sighed, "But I'm gonna get to the bottom of this." The Detective turned to face the rest of the group that had gathered here. "The rest of you, get back to your rooms and hunker down, and pray to God you're not next to be murdered." Thunder roared at the last word. Maybe it hasn't occurred yet that we shouldn't say murder? You were about to say something, but the Butler beat you to it "I'll...I'll check on our other guests." He voiced. Other guests? Everyone was here, the only person missing was the Colonel... You hadn't seen him since last night. Before you could ask the Butler where the missing guest was, the Chef turned to the doorway. "I'll get back to cooking, all this death made me hungry!" He added with a note of blasé. You looked to the Mayor, and he looked back at you with heartbroken and lost eyes. "I...I,I need to talk to the Colonel about this." He spoke resentfully. He was wringing his thumb around the top of his silver cane, he seemed to turn gray as he left.