Marvel's ever-lovin', blue-eyed Thing is a classic everyman hero in a monster's body. While Ben initially struggled with his transformation - and has had dark periods since - he's come to accept his rocky hide, especially since the Future Foundation - a group of young scientists mentored by the Fantastic Four - invented a serum which allows him to turn human for one day a year. Sadly, it's a development that will come with an unforeseen price - one depicted in Fantastic Four #605 by Jonathan Hickman and Ron Garney.
While the Future Foundation's serum allows Ben to become human and enjoy simple pleasures once a year, it later emerges that this is also the only time Ben ages, stretching his lifespan into the far future while allowing a very gradual aging process to subject Ben to the ravages of time.
In Fantastic Four #605, Reed Richards, Ben's best friend and the Fantastic Four's Mister Fantastic, travels to a New York City centuries in the future. Reed and the original incarnation of the Fantastic Four are properly revered as legendary heroes, with the future team line-up consisting of the Thing and his adult nephew Franklin Richards alongside new incarnations of the Human Torch and Spider-Woman. Reed, Sue, Johnny, and Franklin's younger sister Valeria Richards are assumed to have been deceased for centuries, with only the incredibly powerful Franklin left to keep his surviving Uncle Ben company.
Apart from a rocky new beard and the need for a cane, not much has changed about the Thing. Though his former crime fighting partners may no longer be active, Ben continues to fight the good fight against the Skrulls and a variety of other future threats. But while centuries may have passed, the Thing is just as capable of calling clobberin' time as ever, and with Ben and Franklin as team members, the Fantastic Four's legacy remains intact.
The Thing continues to advance in years with each passing century, even being chosen as the speaker of the graduating class of a genuine Future Foundation, their originators the unintentional initiators of Ben's newfound curse. Franklin Richards is eventually tasked with dealing with urgent threats in outer space, leaving Ben alone on Earth. Shortly before his nephew returns to Earth, Thing finally succumbs to his old age between the years 5012 and 6012 AD, leaving Franklin as the sole surviving member of the Fantastic Four.
While the rare day of being human may be enjoyable, it is a shame to see Ben suffering from yet another false promise of peace that will eventually end with the lovable character having to live on while virtually everyone he cares for perishes around him - a detail which is even more tragic in the knowledge that Ben recently adopted two children into his family. A proud member of the Fantastic Four, the Thing nevertheless suffers through a fate he could barely imagine and would never have chosen. Such is the price of being Reed Richards' friend.