Ideas for my defense map

ok I want to make a defensive map based on a boss battle in one game
ok first ill explain how the battle looked in the original game
the boss had rollerblades (ignore the fact that it sounds idiotic)
he was very fast, he setted up bombs and you had to desarm them as fast as posible cause if one of them exploded then game over
well after desarming a bomb you had some time to shoot him with your gun but this was veyr hard cause his outfit was bullet proof you could only harm him by shooting at the top of his head (nearly imposible) getting him from the front intead of chasing his back gave you a better chance to hit him but he was so fast that he could ran over you
The idea was to make him fall down on the ground and then shoot him once or twice

Well and I thought i could make something like thta in my warcraft defense map
But well im not sure if it goes well whatever first listen how it looks now

Player 1 is the bad guy and the other players are the defenders
The bad guy will decide what race to attack (human orc night elf undead naga and maybe some other ones) this will change the arena on what the players will fight (Lorderon, Durotar, Ashenvale, Quealtas, sunken ruins and maybe soem other) and also the type of the unit that shall defend it (marine or rifleman, troll heah hunter, archer, crypt fiend and some other). And it begins
the bad guy sets up the bomb after some time it explodes the defenders have to destroy it before it goes BOOM. If it does well the bomb will damage the nearby units (even the bad guy and specialy the defending building) . The closer the bomb is to the target the more damage si dealt.
Also the bad guy has a bomb in his body that will explode 30 minutes after the game starts
So the victory conditions are
Bad Guy wins when
-Main Building dies
-30 minutes are up
Godo guys win when
-bad guy dies

So well im kinda thinking it needs some more ideas and all
Well i was thinking when all defenders would be near the main building and only one would go chase the bad guy then the good guys would surely win cause the bad guy would be chased and he wouldnt be able to set up a bomb cause they would attack him and even if he would ste up one bomb the good guys would destroy it instantly

So i think my map needs some ideas tips
Hey guys give me some suggestions (any suggestion that will be used shall be in the map credits)

heh lol. sounds like it would be fun to play, im not quite sure if i read the post right, but did you ask for any triggering help?

oh i forgot
sorry guys i know this is for triggers
but well i just dont know where to put it
well if you have any suggestions just tell me something about the triggers to use (if your suggestion uses them)