Consider Tiger and Edge to be the toughest Bosses of the main mission, with the exception of the Geyser 1 battle with Lynch and his collective backup troops. Tiger has brute strength and can soak up lots of bullets, while Edge (formerly known as Edgey in the arcade version) uses acrobatics and speed to dodge shots and catch you off-guard. Get a feel for when Tiger will throw or swing objects in the area at you, and take cover accordingly. However, Edge is a greater threat of the two due to his lightning speed. Very good players can deflect his Naginatas with accurate shots. You shouldn't have to worry about being double teamed, but if given a choice, you should be more cautious of Edge.