Space Crusade - Tactical Skills

Space Crusade is a bit like the A-Team where everybody just stands there and shoots. On top of that, Alien event cards do random damage, so if there is only 1 Marine player, they get mauled by the cards alone.
Some less random, more skillful house rules, the first 2 are the most important:

1. Overwatch: Each Marine chapter gets 1 Overwatch token. Each Alien unit type (Grechkin, Ork, Android, Chaos, Dreadnought, not Genestealer) gets 1 overwatch token each. The miniature with the token may fire once during the turn of its enemy at any target that moves in its Line of Sight. If the target is out of sight after moving its first square, it cannot be targeted. Dreadnoughts may only fire their least effective weapon (Heavy Bolters) on Overwatch. The token is placed beside one miniature at the end of the player turn, and removed when a miniature fires on Overwatch, or at the start of the player's turn. (Overwatch favors the defender, but also those with the most heavy weapons. If the Dreadnought got to fire all its weapons twice in one turn it would be unfair, so just the bolters.Overwatch and the corners rule below provide a tactical puzzle in each combat turn, a bit closer to Space Hulk. So clever manoeuvre becomes as important as firepower in Space Crusade.)

2.  Cover on Corners: If you get shot and you lose a life point, but you could move 1 square North/South/East/West to be out of Line of Sight of the shooter, roll a white die. If the result is 1 or 2, 1 lifepoint is instantly restored. (Hugging corners provides protection. So skillful tactical planning is rewarded. You can outflank your opponent so he has no place to hide.)


3. Alien Champion: The Chaos Commander has 3 life points, but the Marines get 3 opportunities to disregard Encounter cards (before any dice rolled) per game. (Less randomness, big help if only 1 Marine Player, plus the Aliens have a real Commander.)

4. Exploding Red Barrels: Each player in random order gets to place one red and one blue 1" square wooden block "Barrel" at the start of the turn on any board square.  Barrels have armor 2. Only Red Barrels explode like a rocket launcher when destroyed. Red and Blue Barrels block line of sight (see rule 2) and miniatures cannot move thru them or into their square. Blue barrels merely block LOS and movement.

5. Flamethrowers: The Flamer is a Missile launcher, but you place a marker in all 9 squares affected. Re-roll the dice again to attack any friend or enemy who moves into any marked square. Flame markers block LOS, including corners. Remove the markers at the end of the Alien turn. If the Flamer is fired in one turn, it cannot be fired on the next turn.
A Chaos Marine will die in the outer 8 squares of a Rocket/Flamer blast if either of the 2 red die is a 3, a 4 in 36 (11%) chance. The Flamer Marine can't get attacked from behind, but he or the Red Barrel can be shot (both 8% chance with a bolter, 39% with the missile launcher). The Chaos Missile launcher can't see the barrel, but has a 89%
 chance of surviving the flame if he walks into it, or he could go on overwatch instead, trapping the Marine, who has a 39% of being killed by the Chaos rocket if he moves, and a chance of getting killed if the rocket destroys the Red Barrel. The Marine can't fire 2 turns in a row either, and he can only move 4 squares, so the Marine has roughly a 50% chance of surviving the next turn. He should have fired 2 squares in front of him, for a 1 in 3 of killing the Missile Launcher, the main threat. The Ork has a roughly 1 in 3 chance of surviving the Flamer if he doesn't move.
"It it better to light a Flamethrower than to curse the darkness" - Amnesty International

Coins would do as markers. Or translucent red bingo chips. (The Space Crusade Terminator rules in White Dwarf 134 have the Terminator Heavy Flamer as 2 red dice, 9 square pattern with no ammo restrictions. So the Flamer is almost officially sanctioned. Note: If the flamer can fire every turn the Aliens will be forced to run thru the flame to stop him, with obvious heavy losses. You can use the Plasma Rifle as the flamer, or buy some flamers as "Bits" on eBay.)

6. Facing: Optionally, all miniatures must face N,S,E,W, determined by the miniature's head. If the defending miniature is attacked in Hand to Hand from the single front square, the defender may re-roll one die of their choice. If the defending miniature is attacked in Hand to Hand from the single rear square, the attacker may re-roll one die of their choice.

These rules allow you to take up a defensive position behind corners or barrels with overwatch, standing shoulder to shoulder, using rockets and flamers to break open enemy defensive positions.

I love it when a plan comes together!