25Can – Dormammu
The most obvious choice to succeed Thanos as the franchise-wide big bad, Dormammu is one of the most powerful beings in the MCU. Not only does he have a penchant for operating in the shadows – manipulating lesser beings, like Kaecilius, to do his dirty work for him – but
his mystical powers are far greater than Thanos’ natural, non-Infinity Stone-derived abilities.
Dormammu has only appeared briefly on-screen in the MCU, in 2016’s Doctor Strange – and Earth’s Sorcerer Supreme managed to defeat him single-handled, which undermines his intimidating aura, somewhat.
Make no mistake: if Dormmamu were to unleash his full might against the MCU, it would be an “all heroes on deck” scenario.