Rushmore (also known as Rushmore1673) used to be a DB Writer. But due to poor reviews and harsh feuds with more popular writers (such as Lady-n-Gentleman & Wildgun-Edge), he was excommunicated from the group. With people taking the news with a bigger deal about it then it should be. (The biggest overreaction was a writer making a phony DB Host Royale Moveset for him, thanks Meta! -_-)
After being fired, a ton of writers began taking battle ideas away from him (Darth Maul vs. General Grievous & Spider-Man vs. Blue Beetle done by Dimension-Dino as example.) After that, he left dA for awhile claiming to be studying for SOLs, but several accounts have been going around trolling with other writers, leading them to believe Rushmore is behind the "sock puppet" accounts. But there was no proof he's behind the madness.
During his studies, he planned on finding a perfect battle to spike his framers. He ultimately found perfect fight in Wildgun-Edge's "Chief Thunder vs. Black Panther."
When he completed the battle, he posted it to dA.
Everyone in the community was shocked to see not only Rushmore has returned, but that he had stolen a battle for another. This has brought an outraged in the community, which lead to more journal posts about his "crimes" and most of his loyal friends leaving his side.
Then one day unexpectedly, his account was deactivated. This was a bright day to the DB Community, but it was unknown and why he just left without saying goodbye. Some believe with all the reports sent to dA by the DB Community, dA must've kicked him out, but others believe he just left to find another social media site to post his work. Anyone doesn't know what exactly what went down, but what we knows is that he had left a mark on the DB Community history and has brought them closer together then ever.
In Company Takeover lore, he is the final boss and the buyer of Station Management, technically their new owner and boss. He, alongside Kevin Gareth and Boris the Bulk have taken over the Cosmic Station and have reeked vengeance apon the hosts for his death. Hosts were shocked and angered by the action, so many tried to take matters into their own hands and assassinate their new boss (Wildgun-Edge, Deadpool, and Discord particularly), but have failed due to his new connection with the station's deed.
There was no point to try to kill him, so many (Like the Gentleman) just gave up and submit to his new power. But with some inspiration (A rough talk with the Lady to the Gentleman and his future-self to Madness Abe), the hosts banded together and try to stop Rushmore from his tyranny. But due to a battle scene not being completed, it is currently unknown who have won the Revolution between the Hosts and Rushmore with StrexCorp.