Space Invaders V2
-----------------

By Alan Bond.



On-going waves of invaders that get harder (they shoot more bullets
each level)

Same amount of invaders as the arcade (55), two rows of "troopers"
and "warriors" and one row of "commanders". They are a little squashed
looking, but area wise it's correct.

The invades move in formation next to each other and never break away
from the pack. One single invader on its own is enough to make the whole 
pack change direction (like the arcade)

55 speeds for the invaders, they start off slow but get faster towards 
the end of the wave (last one is tricky!), also the pulsing drone sound
for the invaders speeds up (again,like the arcade) ;-)

Invader bullets that don't interfere with the invaders movement or your 
own bullet.

Bullet vs bullet collisions are set to: 70% pass each other, 30% both 
explode (this stops any stalemate situation)

The UFO.

Bases that disintegrate.

Lives and a game over, also an instant game over if the invaders reach 
Earth!

Arcade sound FX and the real arcade cabinet's marquee art (ripped from 
MAME)


Bugs
----

Sometimes the level won't end :-\ Doesn't happen often..... I don't 
know why either. It could be if you shoot an invader just as it changes 
L-R direction, and it doesn't count as a kill.

Shooting an invader bullet at point blank range kills you (rockford that 
it).This is because of the "group item doesn't know about walkable-over bug" 
(This might be fixed in 3.2.8)


