A few misable objectives here so I'll map out the mission. After you kill the leopard, pick up your friend and carry him to the car on your map. You will be attacked by another leopard a few times along the way. Make sure you put him down by pressing A again and shoot him in adrenalin mode til he runs off. The leopard dies after the second attack if you do it right. Once in the car look right and kill the rhino before he gets you. Head down the huge cliff and kill the mad elephant and rhino when you get to the bottom. Cross the river and follow it south, sneaking/running past the elephants. There will be a path on your right when you are directly across from the X on the map. Kill the Leopard when you reach the monkey. Continue towards the house and as long as you finish under 30 mins the achievement will pop.