https://youtu.be/2j2p3b3hv8Y
All you need is
1 Halqifibrax to have Colossus+Herald of the Arc Light, it means a 1 card combo (2 with Jet Synchron discard). Watch the video for combo tutorial. Colossus is banned on TCG tho, so sad. If you wanna splash it to another deck, just use that Halq lineup + Dragondark, Dragonhawk, and Colossus, you'll end up with the same board.
If you're new to the Thunder Dragon playstyle, the aim is to summon Colossus/Titan and gotta max out the ratio for Dragonhawk, Dragonroar, Dragondark, and regular Thunder Dragon, don't forget to play the Thunder Dragon Fusion spell too. Then you can play the rest of Thunder Dragon cards at 1 or 2 copies. The support usually used is Allure of Darkness, Gold Sarcophagus, Batteryman Solar/Aloof Lupine, Chaos Space (and its target like Wyverbuster/Collapserpent), and lastly Verte Anaconda/Cross-Sheep.
Pros: New fun approach of Thunder Dragon and splashable.
Cons: Weaker than the Chaos version, Colossus is banned in TCG.