6max 10/20PLO 2.1k effective (Villain is a complete unknown) villain raises to 50 from utg I flat out of the big blind with AsJsTx5x flop is 8s6hKs villain bets 70 into 110 I call turn is a 3s completing the flush I ck he bets 190 into 250 I make it 575 he calls river is a 3h ??? I feel like it's obv most of his range is made up of flushes and my standard is to bet. I had the feeling he wouldn't expect me to continue with the blocker once the board paired Which made me feel that my bet was thin. This is not a spot that I'm completely comfortable in and was looking for some insight.
My thoughts... Betting 1k into 1.3k seems optimal to me BUT vs a tough opponent I'm in fear of chk deciding and making a mistake by folding vs a small flush or a top 2 type hand that didn't believe me on the turn and has the perfect hand to turn into a bluff.
All things concluded I believe it is a standard bet of 1k on the river simply bc Villain is too flush heavy to not try to go for value. Very interested to hear something I haven't thought of or new ideas or theory's.

Thnx,
Chaseuk21