Well if you only want the multiplayer side of the Call of Duty: Black Ops 3, your wish is granted. For a limited time of course, there is always a catch.
Activision has announced that there is now a multiplayer-only pack for Call of Duty: Black Ops 3 and if you have the pack, you can get access to the Public Ranked Multiplayer matches. You will have a level cap of 55 and you can access to Weapon Paint Shop, Gunsmith, Arena, Freerun, Theater, and the Black Market.
Zombies game mode, Campaign game mode, ability to play in Multiplayer custom games, ability to Prestige (your level will be capped at 55 in the Starter Pack), access to mod tools or modded content (once released), access to unranked server browser (once released), ability to Fresh Start your profile and ability to access Dead Ops Arcade II and Nightmares mode are not included in this pack.
Call of Duty: Black Ops 3 - Multiplayer Starter Pack is now available on Steam but, for a limited time: February 29.