The idea is a tower defend where you build on the enemy's path to get them to follow a maze that you build (See warcraft 3 maul maps).
If you're unfamilar with mauls then here's a guide:
Red represents where the enemies spawn, the numbers are the 9 player starting locations, green is where the enemies need to get to, blue and white is where the enemies can move, most tower defences only let you build next to the path (The black), but in a maul you build on the white locations, where you can build complex mazes of towers that the enemies have to walk through.
There are other game modes with the maul, the above map would be co-op, then there's last man standing where each player has their own lane to manage, and finally there's wars, where two teams build defences on each side of their map, with their spare money they buy troops which are sent toward the other enemy's base.
To mix things up, each player in my version of the game has their own online profile which levels up the more they win, which gives them points to spend towards minor upgrades (Like increased build rate or more damage) or buy a new set of towers entirely (There are elements, like slowing towers, splash damage towers, gradual damage towers). This is of course a game model similar to what league of legends uses.
If you're unfamilar with mauls then here's a guide:

Red represents where the enemies spawn, the numbers are the 9 player starting locations, green is where the enemies need to get to, blue and white is where the enemies can move, most tower defences only let you build next to the path (The black), but in a maul you build on the white locations, where you can build complex mazes of towers that the enemies have to walk through.
There are other game modes with the maul, the above map would be co-op, then there's last man standing where each player has their own lane to manage, and finally there's wars, where two teams build defences on each side of their map, with their spare money they buy troops which are sent toward the other enemy's base.
To mix things up, each player in my version of the game has their own online profile which levels up the more they win, which gives them points to spend towards minor upgrades (Like increased build rate or more damage) or buy a new set of towers entirely (There are elements, like slowing towers, splash damage towers, gradual damage towers). This is of course a game model similar to what league of legends uses.