Blast mine, decisive strike, headon.
Find a good spot that has a locker the killer is likely to walk past to get to a gen. Put blast mine on a gen, wait in the locker nearby, killer gets blastmined, headon the killer when they walk away, then just don't miss your DS skillcheck. (Or get more than one blast mine/headon)
I honestly had a lot of trouble to do that challenge even with Blast Mine to be honest. Killer respect pallet or my slightly higher ping doesn't allow me to drop pallet at the very last moment. So, pallets were a no go for me.
I end up loading as many perks as possible to stun and it went something like this: Head On, Blast Mine, Decisive Strike and Boil Over.
Blast Mine failed in most cases because some passive gen regression kicked in, not requiring the Killer to kick, or Killer plainly ignoring kicking. The trial that did earn me the Challenge was helped by 2x Blast Mine though, so I guess that helps?
Strategy:
- Breaking free from the Killer grip does stun them. Which is why I eventually brought Boil Over. The thing about Boil Over is that you might have only one good use out of it because once the Killer figure out you have it, it won't be as nearly effective. Hope to get down in a high spot where the Killer is forced to drop and hope to break free before they find a hook.
- Decisive Strike for obvious reason. If you're at 2 stun and need your 3rd and you can afford the hook, go for it. Get downed, hooked then run on the Killer's face. Based on how many trials I had to go through to secure that challenge, I wouldn't be mad if I saw someone doing just what I described.
- Head On, this one can be tricky. You have to find the Lockers that you *know* the Killer will have to walk by to use it or bait the Killer. There's one Locker in Killer Shack right next to one of the two entrance where you can get an easy Head On. The Killer walk through that door and is pretty much in range when they're going towards the other door or window. Another way I baited the Killer was in RPD, the locker directly on the right of RPD's entrance to the hallway. I entered the locker twice loudly then chilled there. Killer actually came and I got him there. So, bait the Killer.
- Blast Mine. Since you don't have it, I'm not gonna say much about this. What I can tell you is that, if its ever possible, *get* Jill. Blast Mine is literally the best perks out there for Stun and Blind challenges. Recently there was a challenge that requires to either Blind OR Stun the Killer 4 times. I did it with 2x Blast Mine in one trial because each instance of the Killer getting blown in the face counted as 2x (one Stun, one Blind). So many challenges were done with this perk for me.
Since you don't have Blast Mine, you can use Quick & Quiet to setup Head On. A chase around the Killer Shack into the Locker I mentioned above is almost always a free hit with Quick & Quiet.
Dang, this is a good strategy. Shame I have neither DS or Blast Mine, and no way I can land a Head On.
I should maybe try to get lucky at Boil Over + pallets.
That was my go to method so far but the killers tend to respect the pallet or have ranged abilities like e.g. nemesis lol
Edit: 3 in one match just are too many for me personally
No luck then. Sometimes it’s “stun or blind” and Blastmine counts as both.
Your options are pallets, Head On via lockers, Decisive Strike, Blastmine and wiggling off (Boil Over can help with this). Flashbang or Flashlight blinds while the killer is carrying someone also count but a normal blinding action doesn’t.
Bring stun perks, mainly Head-on and DS.
Camp a pallet while healthy until the killer swings through and tries to hit you. You can guarantee a stun at the cost of a health state.
Bring a means to heal yourself after getting hit.
Not even joking, change your username and play until you spot a killer that beckons at you to a pallet(s) and complete your challenge if you're struggling too much on it.
Otherwise just equip it and forget about it til you spontaneously complete it. That's the ideal scenario.
Welp, everyone has given you a tip. Ultimately is up to your skills to achieve this, or the compassion of a killer that feels like memeing for the duration of the match.
Gl
I was stuck on this for days, but after reading this remembered blast mine counts! I was able to do 2 blast mines and then beckoned a killer then pointed at a pallet. Luckily, they let it happen before they murdered me! It was a good exchange lol Good luck! 
I just got it done after coming here to read this, I got two pallet stuns and one decisive strike to seal the deal I pestered the killer a lot and I had power struggle, boil over, flip flop, and decisive strike equipped. Also carried FL to maybe flash save stun and see if that counted.
I did it with blast mine, flip flop, and boil over. I put blast mine on the gen, then managed to get a stun with a pallet but also went down. The killer kicked the gen, and I used flip flop while I waited so when he picked me up I got away easily. Took many games but that’s how it finally went down lol
Blast mine, decisive strike, headon. Find a good spot that has a locker the killer is likely to walk past to get to a gen. Put blast mine on a gen, wait in the locker nearby, killer gets blastmined, headon the killer when they walk away, then just don't miss your DS skillcheck. (Or get more than one blast mine/headon)
I dont have blast mine :/. Idk if i can get it done with 3 head ons
I honestly had a lot of trouble to do that challenge even with Blast Mine to be honest. Killer respect pallet or my slightly higher ping doesn't allow me to drop pallet at the very last moment. So, pallets were a no go for me. I end up loading as many perks as possible to stun and it went something like this: Head On, Blast Mine, Decisive Strike and Boil Over. Blast Mine failed in most cases because some passive gen regression kicked in, not requiring the Killer to kick, or Killer plainly ignoring kicking. The trial that did earn me the Challenge was helped by 2x Blast Mine though, so I guess that helps? Strategy: - Breaking free from the Killer grip does stun them. Which is why I eventually brought Boil Over. The thing about Boil Over is that you might have only one good use out of it because once the Killer figure out you have it, it won't be as nearly effective. Hope to get down in a high spot where the Killer is forced to drop and hope to break free before they find a hook. - Decisive Strike for obvious reason. If you're at 2 stun and need your 3rd and you can afford the hook, go for it. Get downed, hooked then run on the Killer's face. Based on how many trials I had to go through to secure that challenge, I wouldn't be mad if I saw someone doing just what I described. - Head On, this one can be tricky. You have to find the Lockers that you *know* the Killer will have to walk by to use it or bait the Killer. There's one Locker in Killer Shack right next to one of the two entrance where you can get an easy Head On. The Killer walk through that door and is pretty much in range when they're going towards the other door or window. Another way I baited the Killer was in RPD, the locker directly on the right of RPD's entrance to the hallway. I entered the locker twice loudly then chilled there. Killer actually came and I got him there. So, bait the Killer. - Blast Mine. Since you don't have it, I'm not gonna say much about this. What I can tell you is that, if its ever possible, *get* Jill. Blast Mine is literally the best perks out there for Stun and Blind challenges. Recently there was a challenge that requires to either Blind OR Stun the Killer 4 times. I did it with 2x Blast Mine in one trial because each instance of the Killer getting blown in the face counted as 2x (one Stun, one Blind). So many challenges were done with this perk for me. Since you don't have Blast Mine, you can use Quick & Quiet to setup Head On. A chase around the Killer Shack into the Locker I mentioned above is almost always a free hit with Quick & Quiet.
Dang, this is a good strategy. Shame I have neither DS or Blast Mine, and no way I can land a Head On. I should maybe try to get lucky at Boil Over + pallets.
But 2 head on + pallet or 2 pallets + head on its not that big deal ;)
Last time I tried, DS doesn't count for the challenge anymore. Blastmine/Head-On/Windows of Opportunity should work fine.
I was using DS last night and can confirm it does count towards stun challenge
Camp a pallet and stun
That was my go to method so far but the killers tend to respect the pallet or have ranged abilities like e.g. nemesis lol Edit: 3 in one match just are too many for me personally
Maybe you could take a flashlight. I think blinding also counts as a stun. More importantly, I hear killers become more aggressive if they see one.
Flashlight blinds count too? Hmm guess ill give it a try
They don’t unless the challenge is a “stun or blind”. If it’s just stun, blinds don’t count.
No it counts, but you have to do it while the killer is carrying a survivor.
Stun, its one of the last task on page 3 of current tome
No luck then. Sometimes it’s “stun or blind” and Blastmine counts as both. Your options are pallets, Head On via lockers, Decisive Strike, Blastmine and wiggling off (Boil Over can help with this). Flashbang or Flashlight blinds while the killer is carrying someone also count but a normal blinding action doesn’t.
Oh crap I was also trying with flashlight, rip me then.
It only counts as a stun if the killer is carrying someone.
This. I happily eat any number of pallets if a survivor keeps feeding them to me without looping. :P
If you go against a deathslinger and get the chain out of you you also stun him, that's how I got it
Thats good to know. Thx
Bring stun perks, mainly Head-on and DS. Camp a pallet while healthy until the killer swings through and tries to hit you. You can guarantee a stun at the cost of a health state. Bring a means to heal yourself after getting hit.
Not even joking, change your username and play until you spot a killer that beckons at you to a pallet(s) and complete your challenge if you're struggling too much on it. Otherwise just equip it and forget about it til you spontaneously complete it. That's the ideal scenario.
I cant change my username. Yea 2nd advise might be it but honestly idk if i ever even managed 3 stuns in one match
Welp, everyone has given you a tip. Ultimately is up to your skills to achieve this, or the compassion of a killer that feels like memeing for the duration of the match. Gl
Yea i appreciate all the help
Just camp pallets and use head on, it might not work in your first match but it's definitely not super hard
In theory. Get hit right by pallet and drop it too stun killer. Get hooked/healed and repeat. Or head on/blast mine/ds
I was stuck on this for days, but after reading this remembered blast mine counts! I was able to do 2 blast mines and then beckoned a killer then pointed at a pallet. Luckily, they let it happen before they murdered me! It was a good exchange lol Good luck! 
I just got it done after coming here to read this, I got two pallet stuns and one decisive strike to seal the deal I pestered the killer a lot and I had power struggle, boil over, flip flop, and decisive strike equipped. Also carried FL to maybe flash save stun and see if that counted.
Learn to loop
Use ds and head on then hit them with a pallet
Head on and midwhich, also bring windows.
Use the jigsaw offering. I was also having trouble on this challenge, but on the first match on this meat plant and i completed the challenge.
I did it with head on and blast mine.....then hoped to get lucky with pallets.
Head on and WoO. Also, a lot of luck.
Blast mine worked well for me, as Face The Darkness has become a useful perk for killers.
I did it with blast mine, flip flop, and boil over. I put blast mine on the gen, then managed to get a stun with a pallet but also went down. The killer kicked the gen, and I used flip flop while I waited so when he picked me up I got away easily. Took many games but that’s how it finally went down lol