The highest killstreak would be the amount of kills you can get on that match
Attack Dogs and the Gunship are both the highest killstreak reward at 11 kills.
25
you can't :(
A "Kill Joy" is a medal is received after killing someone that is on a killstreak. A killstreak is consecutive kills without dying. It is always satisfying to know you killed someone that is having a good time :)
The highest rank in Halo: Reach is Inheritor.
11 killstreaks: attack dogs or gunship
The joint highest killstreaks are helicopter Gunship and Attack Dogs both on 11 kills.
It is 11 it is either attack dogs or a gunship
Get a 100 killstreak
Well, in CoD4 killstreak rewards end with a helicopter after 7 kills. The highest scored by a person ever, I do not know. It is hard to tell as many players glitch, hack or cheat the game and therefore you cannot use their numbers as a basis for information. My highest killstreak is 27, and it stopped there because the game ended. I was 27-0 with the potential to keep going, so it is tough to say what the highest killstreaks are. But there are people with 40-50 killstreaks.
The highest possible rank in Halo: Reach is Inheritor (20,000,000 cR) but the highest rank with Grades is General which has FOUR grades (grades are credit milestones which are included with all ranks up to General).
NOPE! It's a 3 killstreak.