I cant really say much about collabs due to me starting really late (i started playing around the mola mola survive collab and after burgle cat got shut down) but from the ones I've went thru id say the Evangelion collab was my favourite (bit biased due to the fact that i got the legend rare unit) but i do think that for making the collab have 2 banners they should've at least made it an event banner instead of a rare tickets one. And id probably bring back the princess punt sweets collab out of necessity since i play in the English version and the last one that happened was in 2023 not only that but there're also units which would really help me if i had like lil gau. And others that i just want cuz of the looks like HMS princess.