Of course I like the GMG arc the most! Its soooooooooooo addicting ^^
And also the battles are very much fun to watch!This arc is mysterious and awesome at the same time <3333
And my second favorite arc is the edolas arc,its also very awesome...
Also,my least favorite arc is the 'Key of the Starry Skies' arc :)
My favorite arc is the tenrou island arc because the grimoire heart comes to attack them which almost killed them. For some reason, zeref is my favorite character in the arc.
My 2nd favorite arc is the GMG.
3rd is Edolas.:)
Honestly, the Tower of Heaven Arc is my favourite, good fights, ending and plot. The current GMG arc isnt doing it for me... The plot is botched and for anyone who is it not a main character *natsu and lucy* gets a nerfed, gagged or ass-cheeks fight! However the anticipation of the dragons involvement does put it in my top three arcs.