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Without the horde of mutated freaks that haunt the bunker, Hollow Ground would just be about navigating the labyrinthine tunnels to find the exit. Enter monsters. This bloodthirsty gang will do their best to blast any ill-prepared mercenaries to bits.

[edit] Monster stats and difficulty

The monster stats are not static. Monsters get tougher as is described in Table 2 (section on Maps, Levels and Difficulty). It works something like this. Each level span has a difficulty multiplier. You can also set the general difficulty level in the Preferences Screen (which is also a multiplier). These two multipliers represent the current difficulty at any given time. Individual stats are expressed as base values. The monsters actual stat is the result of multiplying the current difficulty multiplier with the base value. In the below table I have listed the stat base values. Actual stat values are filled out when the monster is generated.

Monster base stats

Name	Health	Speed	Range	Score
Amoeba	3,000	1.0	-	200
Battle Droid	5,000	0.75	36	3,500
Brain-in-a-vat*	4,000	0.25	-	1,000
Disembodied Mind	125	2.5	80	150
Drone	320	0.80	24	100
Chaos Marine, laser	100	1.25	24	50
Chaos Marine, mortar	100	1.20	16	50
Cyborg Zombie	50	0.75	-	10
Grunt	150	1.25	-	50
Saurant, fire	200	2	16	200
Saurant, poison	200	2	12	200
Saurant, electric	200	2	32	250
Spider, giant	350	1.0	20	150
Spider, small	50	1.75	-	150
Squatter	90	2.20	-	-
Turret	1,200		32	350
End-boss, head	10,000	10	32	25,000
End-boss, body	25,000	-	-	100,000

* Brains-in-a-vat's health is calculated as 4 000 + (1,000 x difficulty) and their speed is calculated as 0.25 + (1.0 x difficulty).

Notice: Additionally, monsters also have a property called randomness. This value is used to control the amount of randomness in monster behavior and properties, so base values are always ballpark figures.

Until someone sits down and writes a proper guide on characters it might be interesting to know that Walter (the marine) makes 10 points of damage per shot with his rifle. This base damage is multiplied with his weapon power-up level. Things are however not as simple as this might imply, at least with the game's missile weapons. First, weapon power-up effectiveness does not increase with one for each power-up. Second, missiles make damage each time they collide with the monster and all missiles collide a number of times before they are destroyed. The best example is Walter's laser, which makes 8 + (2 x power level) points of damage each collision as it passes through a monster. This is the reason why most weapons are more powerful than the base damage seems to imply. Walter does not need to shoot a Grunt 15 times with his rifle at power-up level one to kill it! The exact number of times depend on so many factors that it is best to leave it for another part of the guide.

[edit] Monster damage resistances

The monster stats are, of course, of no real use unless you also have stats for the player characters' weapon damage, armor etc. You can, however, estimate using the base values, the level span multipliers and counting the number of shots that is required to kill a monster at a particular level. On the other hand, monsters have something called resistances, which is another way of saying they are more or less immune to some form of attacks. You need to select the right weapon for a particular monster or your weapon power-ups just won't do you much good. I have listed each monster's resistances and weakness to the five different types of damage in the below table.

Name	Fire	Mental	Electric	Acid	Normal
Battle Droid	50%	75%	x2
Drone	50%	75%	x2
Turret	50%	75%	x2
Brain-in-a-vat		x4
Disembodied Mind		x4