The Roblox game you’re probably thinking of is Build ur Base or something very similar, where you buy weapons and shoot blocky builds/base structures. A few other Roblox games with that same vibe are:

  • Hypershot — fast combat with guns and abilities.
  • Locked 2 — weapon-focused Roblox combat.
  • Build ur Base — base-building plus fighting enemies in a blocky style.

If you mean the one where players literally build a block structure and then destroy it with guns , the closest match from current Roblox results is Build ur Base.