Both of them are easily entertained, but Cesar's worse about it. He'll be obsessed with a singular movie for weeks or months before moving on to something else. Right now in LMH it's Jacob's Ladder but honestly this dude would unironically sit down and watch Brave Little Toaster if you happened to put it on in the same room as him. Mark's a little more selective, but not by much. All of this has to do with the impending restrictions on the film and TV industries as a result of the destruction order. Movies are about to become a hot commodity to anyone intentionally going against this order. Video games as a concept are fucked until home computers become more commonplace.

On that note, since it came out in 1977 and the destruction order wasn't mandated until 1992, Mark's got an Atari lying around somewhere. Cesar probably had one that was thrown out.

It doesn't show, but Cesar's more devoutly religious than Mark. He's just also more prone to making shitty decisions. Mark is still an idiot teenage boy with teenage boy hormones, but when the two are together it's usually Mark taking the role as the voice of reason. (But sometimes they also make each other worse, especially when they were younger)

Cesar bounces his leg when he sits. Mark HATES it. Cesar starts doing it on purpose just to get Mark's hand on his knee.

Mark's usually calmer (on the outside) than Cesar but he's just as much a nuisance when he's bored. Mark and Cesar being bored together in the same room usually ends with Mark throwing the sane man facade out the window and both of them doing some Boys Will Be Boys shit.

Adding onto that sometimes Mark will just pick up Cesar and hold him upside down if he's bored in the same room as him. Cesar doesn't fight it and accepts his fate every time.