If you’re a hardcore achievement hunter, then you’ll probably want to have a go at the Killing Twins achievement in Dead Island: Riptide. The achievements seems very easy, but sadly it’s not, as killing the twins requires you to go searching for them.
Firstly, both twins are located in the same area, the Pinai Ferry, so you don’t need to wait for large proportions of the game to obtain the achievement. Sadly, the second twin is much harder to find, and considering that these guys are toughies, you’ll get quite frustrated if you don’t know where to look.
The first twin is fairly easy to find. You need to go to the northern beach area. There is a life guard shack in this region, which as the first twin in it. He’ll run out of it swinging at you, so you need to be ready for his aggression.
The second twin is a bit tricky to find. You’ll need to search for a large billboard. The part that makes the billboard distinct in this area is the fact that it has a truck on top of it. Check the back side of the board and you’ll find some ladders that lead up to the truck. Climb up, and you’ll come across a sniper rifle and some ammo, along with a meat bait.
Now, look down to the left to see the green warehouse. It has two doors, but they don’t normally budge. What you need to do is throw the meat bait down, which will result in zombies coming out of the warehouse.
Execute these zombies and go down. The twin should’ve come out with the zombies, but if he didn’t, then check inside the warehouse (you’ll be able to open the doors now). Inside should be the twin.
Take him down with a few shots to the head, and you’ll obtain the Killing Twins trophy. If you can’t find him the first time, load the game again after a couple of hours, and he should appear.