Does Tank Trouble Have Online Multiplayer? No, It's Local Only

Tank Trouble (the browser/Flash classic and its later ports) does not support online multiplayer. It's designed for:

• Single-player vs. AI
• Local multiplayer (2-3 players on the same keyboard/device)

If you want online tank combat, look at World of Tanks, War Thunder, Armored Warfare, or browser-based .io games like Diep.io (though not strictly tank-vs-tank).