i am so sorry for this but i'm pretty sure the tattoos were like artistic liberty from the movie director bcs they are never mentioned in the book sjfsdh.
'No one knows how he got out of Azkaban,' said Ron uncomfortably. 'No one's ever done it before. And he was a top-security prisoner too.'
i feel like this implies there aren't top-security cells but top-security prisoners
'Nobody but trained Hit Wizards from the Magical Law Enforcement Squad would have stood a chance against Black once he was cornered. [...] Iā I will never forget it. I still dream about it sometimes.
and even if prisoners could get like, lowered from top security to regular prisoners i think it's pretty unlikely they'd lower their guard on someone like sirius, who they thought was voldemort's right hand man at this point and needed twenty members of the magical law enforcement patrol to arrest (pretty badass i love him)
'You know, most of the prisoners there sit muttering to themselves in the dark, there's no sense in them... but I was shocked at how normal Black seemed. He spoke quote rationally to me. It was unnerving. You'd have thought he was merely bored [...] Yes, I was astounded at how little effect the Dementors seemed to be having on him ā and he was one of the most heavily guarded in the place, you know, Dementors outside his door day and night.
again it's sad but i think prisoners never get to be outside their cells unless for visits, i guess? (how barty crouch jr escaped) but we all know nobody visited sirius... as for the inmates, he would have been surrounded by other high-security prisoners, who were high rank death eaters and i really doubt that sirius, however desperate, would have ever ended up planning an escape with a death eater lol.
'Harry... I as good as killed them,' he croaked [...]
'I don't know how I did it,' he said slowly. 'I think the only reason i never lost my mind is that I knew I was innocent [...] But I was weak, very weak, I had no hope of driving them away from me without a wand... But when I saw Peter in that picture... I realised he was at Hogwarts with Harry... perfectly positioned to act, if one hint reached his ears that the Dark Side was gathering strength again... ready to strike the moment he could be sure of allies... to deliver the last Potter to them. [...] It was as if someone had lit a fire in my head [...]
sirius never tried to escape before that both because he was out of hope and because he felt responsible for james and lily's deaths, so rotting in azkaban was a suitable punishment, no? he only got the actual strength to even try when he saw harry's life was in possible danger and I'm honestly obsessed with this fact. he didn't even escape because he wanted to be free, he escaped with the sole purpose of protecting harry