There are numerous Marvel villains who have been hinted but not completely utilized in the MCU.
Some of these antagonists have been teased as far back as the MCU's first year, while others have only recently been hinted at in more recent productions.
As a result, the ultimate introduction of some of these hinted supervillains should happen sooner rather than later as the MCU expands
There are still plenty of threats in the MCU hiding in the shadows, hailing from varied backgrounds and wielding a variety of different power sets.
As a result, some of these teased villains pose more of a threat to specific individual heroes, whilst others could be as powerful as Thanos the Mad Titan or Kang the Conqueror.
Here is a list of every significant villain who has been teased in the main MCU but has yet to be fully utilized.
The Doctor Strange villain Nightmare was possibly alluded to in Loki season 1 by Agent Mobius M Mobius in an off-handed comment.
horror may be a continuous menace in the MCU who has yet to make his presence completely known, referring to an entire "nightmare department"