Case1:
Actually the Pumpkin Contest was a Reminder Topic of this forum, where anyone could create an account at any time and become a participant in the competition.  Many people here have tried to bring innovation to his work by following the work of many.  In that case if someone has posted more than once then those who post more than once will be considered as multi.  Very surprising and funny.

Case 2:
A bit more ironic in the second case is that we can't use the Bitcoin sign outside of the symbols popularized by these two gentlemen, Satoshi Nakamoto and Bitboy.  According to your research you should have used a different Bitcoin token for each participant.  And the BRICS you imagine is illogical.  If you want proof, I can show you a floor with ten thousand different bricks.

Case 3:
According to your research, if sections or threads of posts from multiple accounts look similar, then they are all multiple accounts. lol

Case 4:
Generally, Christmas is an international public religious event and festival.  Any person, institution, country from any part of the world can express their religious attitude towards different nations.  It is equally recognized everywhere in the world including Bitcoin forums.  If someone respects these religious events by writing or sharing videos, messages, pictures etc. of festival celebrations then it is basically taken as entertaining, educational for all religions.  Then according to your research no one in the forum can post any religious ceremony greetings, images etc in the same section or thread.  Or posts will be considered as multi-accounts.

NB: please @op guys , don't dishonour the forum rules and regulations. Stop the phenomena. Finally I wish you all the best and good health.