Games Like Trench Defender

Trench Defender is an action packed game where you play as a conscripted slavic man that has to defend his trench against hordes of enemy soldiers and vehicles by using a large variety of different modern (and not so modern) military weapons. Purchase upgrades to your trench, collect new weapons and survive through 12 days of relentless enemy attacks, maybe you'll finally be able to go home a hero (instead of in a body-bag).

Features single-player and co-op multiplayer, both LAN and online through a peer-to-peer* connection.

*Important to note is that to host a server for online peer-to-peer (beyond a LAN) you will need to enable port-forwarding in your router, and if you are behind a CGNAT (shared public ip-address) you'll need to use an external program like Hamachi for online multiplayer to work (port-forwarding doesn't work if you are CGNAT:ed).

Detailed game features:
*12 days of successive attacks with different enemies and expanding weapon arsenal for the player
*20 different enemy types (both infantry and vehicles)
*18 different weapons for the player to use (plus trench upgrades which include 2 other heavy weapons)
*single player and co-op multiplayer in LAN or online (peer-to-peer)