It should be everyone. I have this running on my titan and warlock. They have two grenades possible. So I huck one grenade and get a kill and get my little bonus. Then 8 seconds later I huck that second grenade and get a separate kill. But this time no bonus. Or multikills with one grenade. If I take out a bunch of people. One little bonus. I totally agree that something needed to be done but hope this was the quickest thing they could do and that making everything work right will take some time.