Recs.
Updated
SpecsUpdate
Pros
Pro Great single player and online perfomance
The game performs great even with a high number of enemies on screen.
Pro Caters to lots of various playstyles
There are different characters/classes to choose in this game. Each has their primary weapon which can't be changed, and a special ability. The were is also a secondary weapon available, which can be other player's primary weapons once a level requirement is met. As for the abilities, one character sets enemies on fire to provide constant DoT any time she shoots an enemy. Another character gets bonus critical damage, etc.
There are also perks you unlock as you level up which can drastically affect your play style, such as one perk that moderately damages enemies within a block of you once per second. This can be combined with a perk that boosts your weapon damage by 10% for each close enemy for up to 6 stacks. There are tons of different perks, like ones that focus on protecting/healing the core, or slowing down enemies, or maximizing turret effectiveness, so the game allows you to play how you want to.
Pro Unique maps
There are many different levels in the game and the player(s) always have a choice about how to build their maze. The maps themselves usually have a large open area, with a few obstacles to build around in some cases, and the player(s) can place down blocks wherever they want to create unique mazes every time.
Pro Excellent enemy diversity
The game offers drastically different enemies. Some might be slow tanks, while other could be fast and in swarms, but very weak. The Bobbleheads can only be damaged by shooting their crit spot on the top of their head, but they sway back and forth as they move through the maze.
There are also Bosses that show up at the end of some levels, which are very powerful and giant versions of some of the core enemies. They all gain special abilities which makes them an even bigger threat, such as the Hoverer Queen who, like Hoverers, can only be damaged by being shot in the crit spot on its back. However, this Boss will emit something like an EMP Pulse when attacking the player, which will shut down all nearby towers for a couple seconds. This might force the players to adapt to taking shots at it from far away.
Pro Solid tower diversity
There are many different types of Towers. There are Cannons which fire reliably with moderate damage, Focus Beams which lock on to a single target and fire continuously until it dies or leaves the range, Lightning Towers which emit massive AoE damage on enemies passing by, but fires very slowly, and much more. Towers can be upgraded 3 times which increase their effectiveness.
Cons
Con Block/tower limit reduces design choices
One thing that is not ideal is the player(s) start with a limited amount of blocks. You can't design a grand maze from the start as you don't start with enough blocks. You get a couple more blocks at the end of every wave, but it takes a while to get a solid maze going. This somewhat dampens the possible creativity in designing your layouts. There is also a cap on the number of Towers that can be constructed, so it requires you to think carefully about where to build them.
Con Towers play only a secondary role
In this game the FPS aspect is more heavily emphasized, and the towers assist the player more than the player assists the towers. Towers definitely still play an important role, but the player often needs to do a lot of the work, especially for early waves.