After Zerif successful summoning the Black Dragon.. it command to complete destruction of Fairy Tail.
The Dragon is too strong and no one can't stop it because of this Marakov has no choice but to stop it on his own brute. Sacrificing himself to let his children escape from the monster. Now could this be the last scene we will see the Old Man Luffy version? I think so its the last stand from him.
The Black Dragon Apocalypse Acnowlogia
(Marakov to Fairy Tails)
"You'll understand someday...My Shitty brats, full of pride the answer lies in each
and every one of your hearts Now Live On Into The Future"