How to parry in blue slime boss level?

[Riflas]

There is no pink marks

[Shadowspaz]

When he becomes bigger, there are three pink question marks that appear around his head.

[celerypie]

when he transforms the first time there are 3 pink questionmarks you can get in a parry chain over him.

[Gilded]

when he goes bigger 3 question marks appear around him, parry that

[Riflas]

Ahhhhh i see thanks