Upgrade the knife first it gives 120% for every kill. Unlock first level of crossbow Don't unlock other weapons until later stages when knife is fuuly upgraded Once you get them use traps and poison darts to doublle your money on every kill. Caution. Once you poison a target it will release from the trap. Training: try to get the trainees trapped, then kill any new attackers to get lots of money before the mission ends. Don't clear attackers around the trainees, it will release them to complete the mission. Mines are critical. Clear the area yourself instead of with the tower for higher money value. Use archers first for the towers. They're efficient and you won't need them often. Leave the orc defenders behind when you can. They kill attackers that could be more money for you. I don't use any armor untill the final inspector because they slow you down. The last armor increases your speed by 5%. Try to upgrade your speed early. Run away from crowds and try to fight attackers one at a time. I've never found a need for calling all the nearby attackers to me. I'll go to them when I'm ready and trap them as they chase me, so I can poison them later one by one and double my money. Poisoned trolls are a sweet take.