First Anime Review ever, so here goes...
Non-Spoiler Review For Both Seasons, so read without worry (if you want to)
Anime: Code Geass
Seasons: 2
Total Episodes: 50 (25 per season)
Genre: Psychological, Military and War, Mecha, Action, Super power

SYNOPSIS:
The anime starts with the explanation of how the world is divided into 3 superpowers The Holy Britannian Empire, The EU and The Chinese Federation. Lelouch (the protagonist) is shown as a student with remarkable intellect but is an exiled prince from the Holy Britannian Empire, he's the 11th Prince and son of the 98th Emperor of Britannia. He wishes to destroy the Holy Empire namely his father the 98th Emperor for abandoning him and his sister Nunnally and later sets off on his mission after crossing paths with a mysterious girl named C.C.

PLOT/STORY-LINE:
The anime IMO started off slowly the first 3 or 4 episodes but they gradually picked up momentum and maintained it through out the series to the last episode of the 2nd season.
To avoid some potential spoilers, I'll keep it short.
Britannia won the war with Japan and is now in control of it with its name changed to Area 11 the people there referred to as "Elevens". The 1st season R1 was about the start of the rebellion by Lelouch in order to make a world suitable for his younger sister Nunnally to live in peacefully (who is blind and crippled). Lelouch using the code name "Zero" forms an organization with the purpose of defeating Brianna and taking back control of Area 11 (Japan), but it isn't all that serious 24/7 in the anime we do get some comedy relief moments.
The 2nd Season R2 goes further into his plan to destroy Britannia, before I continue lemme say this the 1st episode of R2 may seem confusing but it's the correct sequence (i.e R1 then R2). Things get explained later. After the events of R1 Lelouch and his organization is still battling Britannia but with time Lelouch has to be more careful in his dealing because of some changes in conditions. In R2 Lelouch is shown using his masterful intellect to oppose Britannia while he stays in the spotlight.
Though as one would expect there are plot holes present in the series some being downright stupid, some others that could've been due to not paying much attention, it isn't perfect but comes pretty close IMO.

CHARACTERS/CHARACTER DEVELOPMENT:
Lelouch Vi Britannia (Zero): Is the main character of the series, he had an dual personality throughout the series, one of an easygoing student and the other being Zero who plans for the destruction of Britannia. He is shown to be Prideful, Stubborn and very intelligent. IMO his character remained almost similar (as stubborn characters are usually hard to change) but as he progresses through his goals he comes across great losses be that his missions or people, which changes him and his plans (somewhat).

Suzaka Kururugi (2nd Main): He's the childhood best friend of Lelouch they meet when Lelouch and Nunnally are send to Area 11. He's shown to be caring about others and excels at combat. I'd say his character changes quite a bit because of all the suffering he goes through (you might even hate him at some point), he believes in changing the system for within itself rather than confronting it by violent means like Lelouch intended, this obviously creates a gap between these two.

C.C: She's a mystery girl who gives Lelouch a rather special power when both of them make a contract with each other. She mostly shown doing her own thing (not really too curious about what's happening around her), her main and possibly only priority is that Lelouch survives. Oh, and she loves Pizza... Lots and Lots of Pizza....

ANIMATION:
The art-style was different from what I'm used to but it was watchable, all characters had some unusually long legs and arms. Searching on the internet I came across a term for it "noodle people". You can try searching for "art style noodle people". The action sequence were pretty well animated there weren't many "bad animations moments". Overall I'd say it had decent animation.

MUSIC:
Ah, this...
The OSTs were wonderful and synced perfectly to add to the impact of scenes.
Here are the names:
Madder Sky Ver1 - Main Theme (My 2nd fav)
Across the Borderline
If I Were a Bird
Continued Story Ver1 (also pretty good)
Yuukyuo Seishuka
Innocent Days
Madder Sky Ver2 (I'd prefer Ver1)
Masquerade
Mozaiku Kakera (right in the feels, most fav)
Noblesse Oblige
Nunnally
Continued Story Ver2

Openings:
Colors by FLOW (Ep 1 to 12, R1) (my fav)
Kaidoku Funo by Jimm (Ep 13 to 23, R1)
Hitomi no Tsubasa by Access (Ep 24 to 25, R1)
O2 by ORANGE RANGE (Ep 1 to 12, R2)
World End by FLOW (Ep 13 to 25, R2)

Endings:
Yuukyou Seishunka by ALI PROJECT (Ep 1 to 12, R1)
Mozaiku Kakera by SunSet Swish (Ep 13 to 25, R1) (my fav)
Shiawase Neiro by ORANGE RANCH (Ep 1 to 12, R2)
Waga Rotashi Aku no Hana by ALI PROJECT (Ep 13 to 25)

FINAL WORDS:
This anime was really different for me, really interesting and really amazing. Those constant plot twists had me on the edge of my seat with me left wondering after each episode what expect next, but it wasn't without its bad deals like those plot holes I mentioned earlier but they didn't spoil the fun too much either so it's all good. It also had a pretty good amount of psychological scenes which left me in awe!

FAVORITE QUOTES:
"If the king does not lead, how can he expect his subordinates to follow." - Lelouch

"In their heart, everyone has faith that their victory exists. However, in the face of time and destiny, the act of faith is fruitless and fleeting at best.". - C.C

RATING:
Plot: R1 and R2 combined 9.7/10
Character Development: 8.3/10
Animation: 8.3/10
Music: 8.5/10
Overall: 9.4/10

Remember this is a combined review about R1 and R2
And my first anime review so it might not have included some things