How to Defeat Fiend Prince
Once you have caught this card, you can do all the crazy build I suggest on here. The great thing about this monster is he is non REM. Most Demon teams you can construct just from catching everyday monsters like Vampire Duke, King Baddie, and Chaos Devil Dragon. With Beelzebub as your leader (fully evolved) then you just need to find a Red Sonia friend. There are tons of them out there.
The best way to beat Beelzebub is to have Athena, another non REM monster. She can be beaten with another guide I’ve written. Just be sure to substitute Beelzebub as your leader for another strong Dark monster that you don’t need the REM for like Dancing Queen Hera, Arcane Monarch Vampire, or 5 Mechdragon Combo, Demon Hadar (Hodor) . Of course it takes time to get these, but this game takes time overall.
The Guide to Defeat Beelzebub