The BJ-2 Combat Knife is an all kit weapon featured in Battlefield 2142. It functions identically to the knife in Battlefield 2, killing with a single hit with a very small range, but it now awards the player with the victim's dog tags upon a successful kill.
After fifty kills with the knife, the player earns the Dogtagger Dagger, a knife replacement with a set of dog tags attached to the hilt. The weapon is a cosmetic replacement, and functions identically to the BJ-2.
- Bots will draw the knife and attempt to stab the player if they get too close, and won't pull out another weapon until the player is dead or a significant distance away.
- Both the BJ-2 and Dogtagger Dagger are both made of titanium, according to the "TITANIUM BLADE" text on both knives.
- The blade of the BJ-2 reads "DOGTAG FETCHER 88", suggesting this may have been its original name.
- Likewise, the blade of the Dogtagger Dagger reads "DOGTAGGER DAGGER - M2000".
- Although not directly visible in the viewmodel, the Dogtagger Dagger's textures show that the dog tags on the knife belong to Demize99, the username of DICE gameplay designer Alan Kertz.