Sanctum is a Tower Defense game (utilizing the Unreal Engine) from indie developer Coffee Stain Studios. While the mazing, building and upgrading towers, etc. are all similar to what one would expect in a TD game, players are also given a more head-on offensive approach through the FPS portion of the game.
The game can be played in both single-player and 2-player co-op modes (4-player co-op is in the works). The experience is pretty much the same in both modes with minuscule differences; as such, I’ll only really be touching on the co-op experience. There are three maps available (each with adjustable difficulty settings), which are reasonably varied. The map Bridge, for example, gives players a huge grid which enables them to construct any kind of maze they wish, while the map Mine requires strategic placing of towers or blocks to force invaders to run down paths which contain no available building areas.
These guys need to be shot in the back of the head if you want to bring them down
There are two major phases of every stage: the building phase (where players can build and upgrade towers and weapons) and the invasion phase (where the enemies come and players must try to kill them before they reach the core). In the building phase, to build a tower players must first create a block, which does nothing except block off the invaders. This block can be upgraded to one of several towers with different attributes (e.g. anti-air, splash, anti-ground, etc.) A block can also be upgraded to a Televator (teleporter plus elevator), which allows players to port to it from the overhead display. Televators can be invaluable during the invasion phase, as one can port to a spot in front of the enemies and not have to run to catch up to them. Just as with many other TD games, different towers will be more effective on different types of enemies.
The various upgradable weapons are also more effective on different types of enemies. For example, the sniper rifle becomes invaluable on waves that contain enemies with weak spots which the towers have a difficult time hitting (e.g. the head or back of the head). Players upgrade their weapons with the same resources that towers take to upgrade, so it can sometimes be tricky to balance the two. Upgrading a weapon makes it do more damage and increases the firing time before it overheats and becomes unusable for a short period of time. Upgrading the sniper rifle also adds an extra shot for each level you upgrade it before it forces you to zoom out.
Like any good TD game, there are air phases which tell your maze to go screw itself
I’ve played a good number of TD games, and I have to admit Sanctum is one of the toughest I’ve played. The towers one builds help a great deal with defending the core, but the FPS play of the game is super important for defense as well. It certainly wasn’t tacked on as a gimmick to differentiate it from other TD games; this, here, is a true hybrid of the two genres. The enemies can be real jerks, too. There’s one type of enemy which requires players to hit it in the head to do the best damage, but it constantly wobbles its head back and forth which can make it blastedly difficult to hit. Fortunately, there’s a monster compendium which players can access in the game. It’s particularly handy to consult before a wave containing enemies you haven’t encountered before; it has concise descriptions of enemies’ behaviors and weak spots.
I encountered some very small bugs and glitches in the game (mostly having to do with interface), but certainly nothing game-breaking. All in all, I found Sanctum to be an enjoyable TD game which truly blends TD with FPS. It’s certainly challenging, but not to the point of being infuriating. More maps and the ability to play with more people would certainly be welcome (much of this is already in the works), but the amount of content and enjoyment the game provides is more than reasonable for a mere $15 (or $12.50 if you go in with a friend for the two-pack). If you like TD games and FPS games, I certainly recommend you check out Sanctum.