A mod called Brutal Zombie Siege will allow you to start a war against zombies! Now, every night, zombies will gather in a real army that will besiege your home and try to reach you at all costs.
Mod Brutal Zombie Siege for Minecraft 1.12.2
This is really a cool mod that greatly diversifies the gameplay at night. Now zombies will attack you with waves, while you can get quite interesting loot from them.
1.12.2 – Brutal-Zombie-Siege- Mod-1.12.2