A fine of up to 10,000 euros: Some costumes are prohibited at carnival. It's clear: opulent disguises with a full-body dinosaur costume are out of the question.
If there is a hindrance or danger, this may also constitute a violation of the general duty of care and result in a fine of between 20 and 35 euros. If you dress up as a guard from the Netflix show “Squid Game,” this falls under the ban on masking.