ranged: double nailguns
melee: tail strike
The Centroid is the mechanical scorpion from the Scourge of Armagon mission pack. It is one of the few base monsters to have a melee attack, and so can be useful to drive the player back and engage at range. They have a neat strafing ability to avoid attacks, but to show it off you need to give the player a projectile weapon and the Centroid space to manoeuvre.
A straight rip of the terribly cute cyber-scorpions from mission pack 1. One of the most popular choices for expanding the ranks of the base enemies, and rightly so.
The centroid is:
1. Not another bloke with a gun.
2. Cool. I mean seriously, a cyborg scorpion? Fuck Skynet.
3. Armed with comprehensive – rather than gimmicky – weaponry, including a decent melee attack.
The large bounding box and medium forward speed of the centroid are its limiting characteristics. They will manoeuver adequately around a base map, but deliver their sting primarily because of a generous supply of nails. And although they don’t charge quickly, they can rotate to face the player quite fast. The result is essentially a mini tank, an enemy that advances relentlessly while hosing ammo into the room.
Although plentiful, the nails are weak and innaccurate enough that players can stay in the open if they either keep moving or have good armour. With less armour or more centroids, the player will quickly run for cover to escape the iron hail. Good for cat-and-mouse stalking amongst a cratescape, or place centroids in deliberately empty areas when you want to make the player really feel under attack.
The melee tail strike is there to punish players who attempt to deal with the nailguns by charging rather than dodging, but can also be employed by placing centroids in confined spaces where the player will stumble into them.
In open areas and at medium range, the centroid can detect and attempt to dodge incoming projectiles. Faster projectiles, like the bursts from the plasmagun, are usually too fast for the centroid to dodge. But slower projectiles, perhaps rockets at medium to long range, might miss. The centroid’s nimble strafing also makes them harder to hit, giving them a little longer to spray nails at the player.
Centroids are useful guards; the bounding box, nail barrage, and deterent of the tail strike mean they are likely to discourage the player getting past them to more desirable locations, like supplies on the far side of a room or an escape route.
Generally, use centroids when you want to throw a lot of nails at the player, and force them to throw a lot back or retreat.