Sentry in Marvel Comics is the superhero identity of Robert "Bob" Reynolds, a character known for being one of the most powerful heroes in the Marvel Universe. He gained his powers after accidentally ingesting a Golden Sentry Serum, which granted him abilities such as superhuman strength, speed, intellect, and molecule manipulation, making him one of the strongest beings in existence
. However, Sentry's immense power comes with a dark counterpart known as the Void, a destructive alter ego that represents the darker side of Reynolds' psyche. The Void is a malevolent force that has caused significant destruction and loss of life, and Sentry's ongoing struggle is to control or suppress this dangerous aspect of himself
. Sentry has been a member of the Avengers and the Mighty Avengers, where he is often depicted as the most powerful member but also struggles with his mental health and the consequences of his powers. His storylines often involve his attempts to reconcile his heroic identity with the threat posed by the Void, including moments where he has been trapped in his own mind or erased from public memory to contain the danger he represents
. Notably, during the "Siege" storyline, Sentry, under the influence of the Void, destroyed Asgard and fought against the Avengers before being killed by Thor, who then cremated his body in the sun
. In summary, Sentry is a complex Marvel character embodying immense power and internal conflict, with his heroic deeds often overshadowed by the threat of his dark alter ego, the Void
