He looks the same as 1st dimension does but with some differences. His hair style is a little different, wears a black lab coat, gray pants, black boots, gray gloves, and an eye patch with a scar running over it and a beard which 1st dimension Doof doesn't have.
This 2nd Doofenshmirtz is more evil and intelligent than his 1st Dimension self could ever be. he is power hungry and desires total control of the Multi-Universe first with his robot army led by his robotic platypus then by joining forces with Marceline's dad twice in their attempts to take over
This Doofenshmirtz actually has no qualms about killing those become problems to him to eliminate those that pose as a threat to him or those who disappoint him as he was willing to kill Lien Da an alley of his for this reason.
Alt Doof is one of Marceline's dad's main allies and his most loyal alley that has ever served him. As he was the one who brought Marceline's dad back from his Nightosphere and recruited Uka Uka's previous minions to serve Their new master. Alt Doof is also Marceline's dad's favorite ally, and they are very good friends as opposed to partners. This was cemented when Marceline's dad began playing really seriously after his death
The V Team Island Adventure
Alt Doof made his debut late in the story as a supposed alley of Uka Uka, But his true loyalty was to Marceline's dad as he more or less listened to him. He develops a rivalry with Eddy and Bender's groups especially Scourge, who he tried to destroy countless times. He then tried to murder Lien Da because of her failures and set up Uka Uka to his death by his boss. He then challenged Scourge to a showdown while Doofenschimtz disabled his dimension emulator machine and he lost, but unfortunately he escaped
The Great Time Travel Adventure
During the gap he was making plans with Darkwarrior Duck to bring back his boss. And he brought him back personally and got the other villains to help the trio. He kidnapped the Bandicoots and performed experiments on them as revenge for Scourge's murder of his PlatyBorg. He was alongside Darkwarrior Duck, Marceline's dad and Joker one of the 4 main divas of the gang. He was fought 3rd to last against Dib, Starfire, Finn and Ice King, He put up a good fight but he was defeated and killed leaving Joker and Marceline's dad left for the take. In this story he managed to destroy W.H.O.O.P headquarters but it was fixed by Bender, Skipper and Heloise afterwards
Allies and enemies
Allies: Platyborg, Marceline's dad, the Joker, Taurus Bulba, Suppression Squad, Me-Mow, Savio, Chuckles, the Noid, Professor Hinkle, No Heart, Eggman Nega, Lockdown,
Enemies: Eddy, Scourge, Bender, the V Team, Dr. Doofenschimtz, Starfire, Skipper, Django, Jorgen, Finn, Marceline, Ice King, King Julian, Agent 9, Lien Da, Darkwarriror Duck, Hans the Puffin, Noob, Scorpion, Dib, Bubbles, Lizbeth, Milo, Edd, Darkwing, Gosalyn, Launchpad, Luciaus and his gang, Emperor X, the Disney Angels