I am trying to get Dimir competitive. If you have any suggestions, please give them. Sideboard needs work too, possibly tailor the deck into control?

The deck is supposed to prevent the opponent from casting cards. Using the Siren of the Silent Song, drain their hand until they are picking off their library, which, by the way, has been slowly draining, depriving them of resources or disrupting scrys. The Desecration Demons and the Agent of the Fates are creature control, keeping the skies clear for the Sirens. The Hidden Strings, Triton Tactics, Thoughtseize, and Springleaf Drum are for accelerating your plan. The Bident is useful because their few creatures will be sacrificed away while Pain Seer gets your low mana cost cards for a small fee. The only worry is when you hit a Desecration Demon or a Bident (1/10 chance) but your life total shouldn't be low with all this wiping.

Please enjoy and give feedback. I wish this to be a competitive deck but it needs testing.