From
http://www.mtgsalvation.com/forums/the-game/modern/tier-2-modern/631246-grixis-delver?page=69#c1741

"Wanted to post my list and give some feedback on a few cards that have been asked about recently.

Countersquall - I swear by this in the MD, it's burn plus negate. It's easier to cast than people think, definitely worth the occasional extra self-shock. It's effects aren't always felt in the moment, but in the replays you can see how it helped bring your opponent to the point of Bolt-Snap-Bolt. Damage wins games. (10% of your life total while saying "NO SIR" is amazing")

Dreadbore - I run 1 MD and 1 more in the side. This card makes our even and bad MU's better (Jund/Jeskai Nahiri). It's stronger than people give credit for, but I think this slot will change with the meta.

Kolaghan's Command - I've heard why people run less, but I don't understand! If it's too slow then you are likely in a race situation, in which case burn plus discard or, removal plus discard are great at slowing the opponent's race. I get 3-4 land in >90% of games.

Tasigur, the Golden Fang - Perfectly happy with 3. Gurmag Angler is pretty much the same clock (16 life opponent takes 4 hits for both) but this guy is more expensive and hart to hit T2. So even if Tas took another turn to kill, he usually can come down a turn sooner. Angler just under-performed for me. Tas wins all the games Angler does, but with his ability he provides serious CA and snap targets.

Young Pyromancer - This guy just wins games sometimes. I get why people removed him, but remember the old UR delver decks? He rocked and is still great. Not many decks run anger or verdict nowadays, I could be missing something, but I think he's in a good meta position. - I advocate 2 minimum in the 75.

Sideboard

Rakdos Charm - It comes in more than the rest of my SB cards for sure. Graveyard hate helps counter persist, snap targets, exile the emrakul that hit the yard after Nahiri discarded etc. 3rd mode comes up very rarely; only in the situations where the board is clogged and you have burn in hand, but it has still allowed for some flashy finishes vs Cord and Token decks. Tokens particularly since they use lingering souls and sometimes artifacts (BSkull or Thopter or swords). Overall a great catchall and one that I rarely hate to draw.

Tribute to Hunger - I tapped out my Jeskai opponent on the turn he was going to ult Nahiri, once he did, I used this to eat Emrakul (Usually for Boggles though)

Shadow of Doubt - Can cast this turn 2 unless you have a mountain, it hoses so many decks and supports the land destruction sub-theme. Also counters Nahiri Ult and MANY other important effects. Always cycles when it's bad.

Grim Lavamancer - He just wins in creature match-ups. I might add a second one in the board...Definitely will if chord gets more popular on MODO."