In Gun Game mode, you begin with a handgun. With each kill you get, you move up through various tiers of weapons. When you get a kill with the final weapon, you will win the game. A melee kill, however, will not advance your weapon tier, but puts the killed player's tier down to the previous tier.
The weapon tiers are as follows:
Due to the way the weapon tiers progress, you will often be up against opponents with superior weapons. Therefore, remain in cover whenever possible and make sure you know the strengths and weaknesses of your gun.
Listen for opponents that might sneak up on you from behind, especially if you are playing on a small map. Be aware of your surroundings at all times, and keep your eyes on the mini map, as well.
If you have a slow weapon, stay behind cover and try to use contextual lean to get in a shot before your opponent can hit you.
Different perks are more effective for different game modes. Follow the instructions below to effectively play Search and Destroy, Domination, and Blitz.
Search and Destroy
In Search and Destroy, you will need to either attack or defend a bomb site.
A good offensive strategy is to use Incog (Stealth Perk), Marathon (Speed Perk), Lightweight (Speed Perk), and Extra Tactical (Equipment Perk). Use that additional tactical slot to equip smoke grenades.
Use a smoke grenade to block your opponents' view of the bomb site. Incog will keep you hidden from your opponents, and your two Speed Perks will make sure you get there quickly.
At the bomb site, use another smoke grenade and plant the bomb.
Protect the bomb.
Another offensive strategy is to use Tac Resist (Resistance Perk), Blast Shield (Resistance Perk), Incog (Stealth Perk), and Reflex (Handling Perk).
Fight ranged battles, while relying on your Resistance Perks to help protect you. The Reflex perk, along with a trophy system, will help protect you from enemy grenades, as well. Eliminate your opponents and head to the site to plant the bomb. A teammate can use a smoke grenade at this point, if you want additional protection.
A good defensive strategy is to take advantage of the period at the start of the round when you can change your class. Use Lightweight (Speed Perk), Marathon (Speed Perk), Incog (Stealth Perk), and either Tac Resist or Blast Shield (Resistance Perks).
Choose a position ahead of time that you want to be. Your Speed Perks will get you there quickly, and the others will protect you along the way.
Once there, switch to a different class that will be more effective for defending the site.
In Domination, you will either be trying to capture a control point or defending it.
If you are trying to capture it, use Blast Shield (Resistance Perk), Reflex (Handling Perk), and Extra Tactical (Equipment Perk). Use a smoke grenade with your Extra Tactical slot, so that you can mask your opponents' view around the control point.
If you are defending the control point, use Extra Lethal (Equipment Perk) so that you can have either semtex or lethal grenades. If your opponents get too close to the control point, use the grenades against them.
In Blitz, speed is your greatest strength, whether you are attacking or defending. Therefore, use Lightweight (Speed Perk), Marathon (Speed Perk), and Extra Tactical (Equipment Perk). A stun grenade should be your tactical item, as you can use it to slow down your opponents.