Get a deck with atleast three 3* cards that you will dedicate to winning, example would be
Smokey Cr, you can win with him and not feel like a waste because you gain pills back,
Oxen because you can cut opponent in half and
Mona because she can destroy the opponents card after 4 pills in most situations. After that aim for atleast one 2* so
Gil for overpill and win or
Dreen because she is similar to
Mona. Have one defence card but no more, defence cards slow down the Dt but without one you will lose a lot more games. Aim for one soa, even if its a bad soa like
Spycee you are better off to have one just to be safe, and have one high damage card with base stats, 5 damage min. Tend to never use a 5 star, use 4 stars (2 max) and you should do fine