I'd like to give an in-depth guide of my exact setup that I used in order to gain all 25 grabs.
I would highly suggest using the Spirit. If you haven't bought her yet, I would highly recommend doing so if you have any real intention of trophy hunting in this game.
The best perks to use to attain your goal consists of:
-Surveillance: When you damage a generator, it will have a white aura around it. If it turns yellow, someone has touched it and is likely still going to be there working on it if you don't get too close and they hear the terror radius.
-Monitor and Abuse: Terror radius is reduced even further until you are in a chase, but if you are in a chase you most likely haven't gotten what you were going for, so this perk will help you up to that point.
- Hex: Ruin: This will possibly disrupt survivors on generators if they can't hit the skill checks and notify you where they are at, so you can either show up and grab them or if they ran off damage the generator for Surveillance to kick in.
-Hex: Huntress Lullaby: This is not that useful, but always provides a helpful notification of where the players are if they are failing skill checks because they can't hear the warning on time.
The MOST EFFECTIVE way to get this would be to set up a Spirit class with the Prayer Beads and Ultra-Rare Glasses. These will eliminate your phasing sound and tremendously increase your speed while phasing respectively. Using a Black Ward is extremely helpful for this trophy as it will surely take longer than one game and unless you have a lot of spares, this will require you to grind through a few trees to find both add-on pieces.
So, to recap, once you have this set-up ready, in game you will:
1. Start by phasing to generators randomly hoping to hear them getting started and grab someone.
2. Find generators being worked on and damage them, keeping a close eye on them when you get further away. When they turn yellow, you are likely out of the terror radius range for the survivor and can quickly phase back in and pull them off.
3. If survivors continually evade you in a game when you are coming in from far away, they are likely running Spine Chill or other killer-sensing perks, which will render your setup useless and you'll have to find less capable survivors in another match.
LAST TIP: If you don't play this game with headphones, it will be extremely hard as a Killer. The combination of a headset and no phasing sound means you will easily be able to hear a survivor actively tinkering on a generator if they are there even before you come out of the phase state. You can kind of prod around the generator and if you hit a barrier where there is clearly nothing, that is where the survivor is and you should come out right behind them and press right trigger to grab them.
Good luck all! It isn't the easiest, but it sure is a lot more fair than some earlier trophies have been regarding grinding achievements.