Destroy A Planet

Without going as far as making reality itself collapse, what better way for Thanos to display the power he holds with the completed Infinity Gauntlet than by destroying an entire planet with a single concentrated energy blast?

Ronan teased the idea of destroying Xandar with just one Infinity Stone – the Orb – in the Guardians of the Galaxy movie, but it never actually ended up happening and there’s no confirmation that one stone could actually succeed in achieving that feat.

However, there is surely no doubt that the six stones combined could do it effortlessly and seeing Thanos destroying a planet (maybe Xandar) prior to facing off with the Avengers and company would emphasise the scale of the threat they were about to face and put audiences well and truly on the edges of their seats.