Complex sentence: Blockland features an add-on system to aid users in managing custom content, such as weapons, vehicles, types of brick effects, player commands and game modes which allows users to write add-ons for the game to share with other players.
Split into simpler sentences: Blockland features an add-on system to aid users in managing custom content, such as weapons, vehicles, types of brick effects, player commands and game modes. This allows users to write add-ons for the game to share with other players.