The 24-year-old winger joined Arsenal in a £34m transfer from Club Brugge last month, a Belgian Pro League record, after striking an extraordinary 40 goal contributions (17 goals, 23 assists) in 36 league appearances last season.
It is a steep rise from his struggles at Norwich in the Premier League five years ago, when he failed to break through before going out on loan to FC Twente and Fortuna Düsseldorf and eventually making the permanent switch to Belgium.
Tzolis feels he is now a completely transformed player from the one who last played in the English top flight.
"It was totally different than now. It's always difficult for a team that is promoted from the second division to the Premier League to play high-level football," he said.
"The team, I think, was not really ready for the Premier League, and that makes it also difficult for me to adapt and to play how I could. You can have some setbacks and difficulties. I only learnt a lot of things from this period at Norwich. I have three years in a row that I'm important for my teams, and I have a big role in an attacking part.
"I feel now more ready to be in the Premier League. I developed myself, I improved a lot. I'm not the same player I was in Norwich, 100 per cent. Now it's my time to show that I'm ready and capable of playing in the Premier League."
He hit the ground running upon joining Arsenal, marking his full debut against Girona with a goal, cutting inside from the left before firing into the bottom corner via a deflection. Tzolis wears the number 17 shirt once worn by his boyhood idol Alexis Sánchez, who became one of Arsenal's standout players during four years in north London.
"I knew that he was wearing the shirt of number 17," Tzolis said. "He was a top player for Arsenal, as a left winger always. He's one of the players I looked up to when I was younger, and I see some similarities with him. But it's not the reason I took the number 17. It's nice, though. Alexis Sánchez had number 17, so I hope I will have the same success."
He has also quickly become the man to beat in Arsenal's pre-season fitness tests, according to team-mate Ben White: "Christos has been amazing. He came in, did all the testing, and beat everyone. So he is fitting in really well and everyone is really happy for him to be here."
Tzolis credited arriving in good shape after starting pre-season early with Brugge: "I had the advantage that I started pre-season also with Bruges, so I was already training for two weeks. I came here ready with my fitness level, and I was happy that I could show it here as well."
Arsenal signed Tzolis as a direct replacement for Leandro Trossard, who left for Besiktas in a £17m deal.