In Killzone 3 Multiplayer, you need to use Proximity Mines, to kill 2 players, in under one minute, while playing in the Blood Gracht. Blood Gracht is only available in Guerrilla Warfare matches. You can set Blood Gracht as your preferred map for Guerrilla Warfare in the Main Multiplayer menu. Proximity Mines are automatically unlocked when you achieve Rank 10 - Sergeant 1. Equip this ability at your class selection under the "Explosives" option. You spawn with 1 Proximity Mine in your inventory but you can replenish and hold up to two at any time from an ammo box. Plant any amount of Proximity Mines in the bottlenecks of the two buildings on the map and as long as you get two kills using Proximity Mines within one minute the trophy will unlock. Proximity Mines also remain where they are a