I played my first game with a buddy last night, me the invader and him a single lone marine. End result is, he beat the hell outta me!

I will try to recap the game session as best I can, working off memory here and I don't have the game handy right now to reference cards and such.

We played the first scenario from the scenario book, don't remember the name off hand. He had his 3 cards, I don't remember the names of any of them but I remember what they do.

1 - Ground Assault (?) The card allowed him to move 2 squares and make 3 attacks when he unloaded (he used this allot with his shotgun which also had blow through so he was easily clearing 2-3 monsters on a single turn)
2 - The card gave him 3 cancels (he only used one)
3 - Recon

Now, I know we started off playing totally wrong, he was rolling more dice then he was supposed to and I, for whatever stupid reason, thought the invaders had to be in melee to attack. But we realized our errors in the first room and played the rest of the game correctly, and least correctly on those two issues.

However, he still got through the rest of the board fairly easy. Basically he took on the "flight mentality" and ran away from everything without a problem. I gotta say, movement for the invaders sucks, and so does the whole spawning out of LOS deal! Any monster I spawned were way too far to even get to him, I had almost all the figures on the board, but he made it right before the last room, got fragged (only my second frag!), and spawned right in front of the red door, winning the game. Lame!

One thing he would do, to great effect, was open a door, wait for me to set up the board, then unload on the room pretty much clearing it. I'm not sure what allowed him to do this, but he was pretty sure it was legit. He was even calling it by a name, which I also don't remember. Maybe that was the Ground Assault card.

I don't know, maybe it was just newbie first time errors on both our parts? The game only lasted 2 hours as well, INCLUDING set up! Can anyone here maybe see what we did wrong, aside from the errors we realized at first?

Looks about right. Ground Assault gives you 2 movement + 3 attacks when Unloading, so open door, waste all in sight is definately doable. Didn't he roll any Xs with Red or Yellow die? Did you observe range correctly? Shotgun especially has horrible range, it can miss when attacking an adjacent square as Red and Blue dice both can come up 0 for range. What about ammo use (though probably less or a worry in 1 Marine games)?

1 Marine is generally considered the easiest for the Marine player, since the goal is to escape, not kill everything. When my friend and I play, I'm the Invader and he runs 2 Marines. This makes for a nicely balanced game.

You've already answered your own question.

There were probably a fair share of Invader Player mistakes. If he was relying on the shotgun (it has terrible range) you could have maneuvered to keep enough invaders just out of range to keep him on his toes.

Also-for him to start his turn by opening a door with an unload (ground assault) action, he'd have to end his last turn in front of it. This means he was giving up a lot of LOS in the room/area he was in in order to get the jump on the next Area. When Marines do this you can spawn behind them in order to make them question their next move; Do they Proceed forward even though something is coming up from behind, or do they go back and deal with it, costing them time.

Based on everything you said, I'll also echo the guess that perhaps you were not calculating range correctly.

Also though; One Marine/One Invader is often thought of to lean (balance wise) towards the Marine Player, especially perhaps if the Invader player is inexperienced, because there is less of an ammo problem and because an inexperienced IP might not take advantage of the LOS openings that are inevitable with just one Marine.

However all said, with a little coaching, I'm sure we can help to fine tune your strategy so that you're killing off marines left and right, the way Doom is meant to be played ;)