Block N Load is described as 'Free to Play FPS Game. Face off in a tactical battle where everything you build, destroy, construct, or shoot has a devastating impact on the entire game'. There are six games similar to Block N Load for a variety of platforms, including Windows, Steam, Playstation, Xbox and Mac. The best alternative is Team Fortress 2, which is free. Other Block N Load like games are Garry's Mod (Paid), Overwatch (Paid), Paladins (Freemium) and Warframe (Freemium).
Team Fortress 2 (TF2) is the sequel to the game that put class-based, multiplayer team warfare on the map. One of the most popular online action games of all time, TF2 delivers constant free updates including new game modes, maps, equipment and, most importantly, hats.
Paladins is a fantasy FPS by Hi-Rez Studios, developer of Smite, Tribes Ascend and Global Agenda. It is currently available for PC. As of 2/6/2016 it is in closed beta. When released it will contain small micro-transactions.
Warframe situates players as members of the Tenno race, newly awoken after years of cryo-sleep into a solar system at war. Reborn into a corrupt era, the Tenno are sought by the oppressive Grineer Empire for annihilation.
Warface is a contemporary MMO first person shooter with millions of fans around the world. It offers intense PvP modes, compelling PvE missions and raids that you can challenge with four diverse classes and a colossal customizable arsenal.