Ultimate Assassin 4 needs to have footsteps emit sounds that the guard hears, so guards follow the sound of your footsteps or if you walk/run behind a guard they will turn around. Also, it would be nice if the guards followed bloody footprints and had a better sense of where you were going. It would make the game more realistic and fun.
I love trying to weave around bullets. It's awesome when I run through a hallway with 10 guards shooting at me but I run through and live. Awesome game.
A good strategy for this is to turn your sumo wrestlers into statues and only keep 1 alive. The point is so your enemys can't capture your sumo wrestlers and overwhelm you.