Hey there! Your deck needs a bit of work, it looks like it's running a lot that has fallen out of favor lately. It needs streamlining, and some better cantrips too. First off, Ponder , Preordain , Gitaxian Probe and Brainstorm should replace Portent , Opt , Peek , Thought Scour , and Mental Note . It'll give you much better filtering and allow you to dig for answers more efficiently. Second, if you're running mainboard fliers Stormbound Geist is much more resilient than Sultai Scavenger , and easier to get out too. Warped Landscape isn't amazing in this format.. 18 Lands is correct, but it's best to run more fetches to pump out Anglers quicker (3 Terramorphic Expanse , 3 Evolving Wilds , 1 Ash Barrens and a 9/2 Split for basics, Islands being the 9). Gush makes your late-game so much more powerful, and the synergy with Foil is comparable to Force of Will , so you'll want 3 of each. Snuff Out is also important for your removal suite, which should also include a copy of Chainer's Edict and 2 Echoing Decay s. One or two extra Augur of Bolas never hurt anyone. Finally, you might also want to run Curse of Chains and Dispel .

If you need a resource to check what U/B Delver is running atm, you should look at MTGGoldfish's Pauper Meta review, it'll show you the top-tier lists and give you an idea what you should run.