ATCS

Advanced tactical combat simulator "A combat training simulator pitting mercenaries against vicious aliens."

ATCS is a symmetrical map, with both bases set up in similar places. The map was created by Nicolas "Jex" Jansens and is included in the Tremulous 1.1.0 release.

Slightly forward base
If the human team has earned enough build points, you can build a small forward base in the entrance to the Human Base, where you come to the open. It gives attacking humans a shorter distance to refill their ammunition and also can help to collect kills during stage 1.

Sniper-safe base
It is difficult to create a human base that is sniper-safe, in other words, cannot be shot at by Adv. Dragoons. Any building on a ledge is an easy target, so only turrets and the like should be placed there. Especially the initial Armoury and Medistation, which should be moved away from this ledge.

Ideal positions for the Armory and Medistation are: Both locations are not fully sniper-safe, but are better than the initial place.
 * Move them a bit from from default place, so it stands next to the Reactor
 * Put them into the "other" corner of the default base (ie. not the corner of the reactor).

"Moving" forward base in tunnel
This strategy requires at least a good and quick builder.

The idea is to make a small forward base in the tunnel: a Repeater, an Armoury, a Medistation, one or more turrets or teslas. This is built in the tunnel, as forward as possible without being destroyed by aliens. Of course, human fighters have to defend this base as well! They then push forward in the tunnel; if they have secured a further part, the builder moves his stuff there.

The forward base should only have enough defenses so that the occasionally lucky dretch that makes it to the forward base can be shown the door without having humans shooting at their buildings. If there is an Armoury, other players can also occasionally exchange their weapons for Construction Kits and help building.

The human fighters have to take the main part of the attack. They have the advantage of quick ammo refilling and healing and can put alien base under constant attack. Of course, humans on the other entrance of the Alien base have to make sure that aliens don't push out of their base.

Note: Many players will disagree with building a forward base on a server with the standard 100 build points (BPs), and it is not a good idea to do it at all when aliens are stage 3. Remember, turrets are to protect your main base, Reactor, spawns and Armoury, not players, hallways or remote rooms.

Misc. hints
To prevent a quick alien rush in the first seconds of a match, it's a good idea to first spawn as builder and place a turret in the middle of the base. This is enough to defend against rushing dretches and maras; without it, a lucky alien can get through to the base and wreak havoc.

Placing a turret on top of the upper ramp to Human base because it is a good stopper for tyrants and goons: while they stand on the ramp, humans can fire at them from many places. Of course, this turret will be destroyed pretty often, so it's probably not a good place in sudden death.

Building Attack Opportunities
At the very start of this level, the single turret facing the hall that connects the human and alien bases is a good target for a dretch, if you feel confident about circling/jumping a turret. Once this turret is down, it is much easier to chase and bite humans who are running back to base from the hall.

A very common human building strategy is to make a line of turrets along the edge of the upper level default base. On a server with a lot of defenders, this can be a good strategy, but below 14-16 people, it is possible for a dragoon to jump over the turrets and onto the Reactor. Once there, the turrets cannot hit the dragoon, and it can destroy the Reactor.

Keep in mind that turrets cannot fire through each other:

ex. 1

ex. 2

In ex. 1, all turrets within range are hitting the Alien. In ex. 2, only the end turret is hitting. Attacking turrets from the end like this is an essential endgame strategy for tyrants. Rush up the ramp, take out a turret then rush to safety. Repeat as often as necessary.

Humans
You can build a good base at the top in the first 10 minutes, but a Dragoon can jump up fast and high and destroy the base. Building inside is bad as well because the Aliens can camp outside at stage 1 and head chomp the Humans for easy kills to stage 3.

Aliens
Building in the middle is bad for the same reason as above. Building a Booster on top for a forward attack is good if you have camping Marauders and Dragoons there, ready for a forward attack against camping Humans.