Well any Green fetch would also work as a way to search for Arbor. But if your primary way of dredging through your deck is a Griselbrand activation, I think you probably want to minimize your life loss.
I've also seen lists that run a Bayou/Arbor split so that they can cast both halves of Cabal Therapy in addition to the green anti-hate cards. But Bayou is fairly expensive so its not as budget friendly as just Arbors.
I'd try to find room for Land Grant and Reverent Silence in your 75.
Land Grant to act as additional copies of Arbor in case its not in your opening hand and you need it, fast. Silence to kill Leylines and RIPs immediately after playing Arbor rather than risk it getting wasted/bolted/swords away before you can cast nature's claim.
I run 1 Ashen Rider in my sideboard for show and tell. Apart from that, I try and take apart their hand with Therapies. With the exception of Elesh Norn, Stinkweed Imp trades with whatever they put into play off of a show and tell.
Reanimator is a terrible match up for Manaless Dredge as they can easily grab Elesh Norn which kills all of our creatures.
Sickening Shoal pitching Phantasmagorian is pretty much the only way to remove her once she its play.
Surgical Extraction and Faerie Macabre are probably your best options. You can also run Leyline of the Voids if it gets to be a big enough problem.
Dredge can certainly combo out very quickly, but I find I win a lot of games (even with Manaless Dredge) through being one of the best decks at grinding. I generate a lot more card advantage than my opponents through dredging. Because I make zombie tokens I get more out of trades than my opponents do. And I can shred their hand with Cabal Therapy. Dredge is a very powerful attrition deck. Its not the main plan of the deck, but it certainly can play the attrition game well. Swinging in for a couple of points of damage each turn, you win most races. I've out paced a Belcher decks that Emptied on turn 1 because my zombies are better than their goblins and I win the topdeck war.
Silenus, Drunken Prophet 2RG
Legendary Creature - Saytr Shaman
Haste, Trample RG: ~ gets +1/+1 until the end of the turn, exile the top card of your library. Until the end of your next turn, you may play that card.
Whenever ~ deals combat damage to a player you may exile the top card of your library. Until the end of your next turn, you may play that card.
3/4
Milzio, Wealth of Knowledge 2UUU
Legendary Creature - Avatar
You have no maximum hand size
Players do not lose the game from drawing cards while there are no cards left in their decks. 3UUUt: Each other player discards his or her hand, then all players draws cards equal to the greatest number of cards a player discarded this way.
2/2
Manaless Dredge: stronger vs counter magic. Higher threat and dredger density. Reliant on Draw, Discard, Dredge.
3 major versions:
Fearless = no anti-hate
Green = Dryad Arbor + Nature's Claim + Reverent Silence and uses Griselbrand over Baltrusade Spy
Blue = Force of Will + Distrupting Shoal and uses Whirlpool Rider over Baltrusade Spy
LED Dredge: Weaker vs counter magic. Able to Dredge faster and its easier to get a dredger in the graveyard. Easier to cast anti-hate in post-board games and can use loot effects to dig for them. Being able to cast both halves of Cabal Therapy is much better than only flashing it back. Can generate large amounts of card advantage on the first turn and has more explosive opening hands than Manaless. While not a good option, can hard cast the creatures in the deck, but is still useful.
In short, Manaless is better vs countermagic, LED Dredge is better vs graveyard hate.
Syln of the Depths 5UUUU
Legendary Creature Squid
Islandwalk
When ~ enters the battlefield tap all other permanents.
Other permanents do not untap during their controller's untap step for as long as ~ is on the battlefield.
Discard a card: you may tap or untap target permanent. Any player may activate this ability, but only during their untap step.
9/9
Next: The person featured on and quoted in Last Word
Quln the Bubbling Muck
Legendary land creature - Swamp Dryad
~ is black
Swamps you control have "Bt, pay 2 life: draw 1 card" 2Bt: target creature gets -X/-X where X is the number of Swamps you control.
2/2
I know that feeling, I ran Dredge back in February at a SCG IQ. It ran well except for the final round. I mulled to 4 in games 1 & 2 and still had terrible hands. I had good opening 7s, if I was on the draw (dredger, loot spells, no lands) but my 6, 5, and 4 were pretty bad and I didn't want to risk a mull to 3. It was a match vs RUG Delver which I feel is normally favorable as they have such difficulty removing bridges and Stifle isn't that powerful vs Dredge, but I just mulliganed into oblivion and narrowly missed top 32.
Every other round my deck performed well. The only other game I can remember bricking was a game 3 vs Omni-tell. I was dredging but didn't hit Ichorids and only hit a single Bridge but between occasional Narcos and Therapies combined with my opponent bricking hard as well I was able to stretch the game out until I finally hit a LED and with a flashbacked looting managed to end the grindfest.
From my experience, I wind up mulliganing to death around 1/10 matches. I run a fairly stock Quadlazer list, I just have 3 Breakthrough & 3 Putrid Imp rather than the full 4 so I can have a DR and Iona in the main. Everything else is a 4 of.
Its really rare that I ship a hand. I'll pretty much only do it if I have absolutely no way to discard a dredger, even if that way is to timewalk myself so I can discard to max handsize (though that I only do if its against a slower deck or if my opponent mulled down a lot). I'll keep 0 dredger hands if I have some loot effects.
Sorin, Innistrad Noble 1WB
Legendary Creature - Human Advisor
Vigilance
Whenever a creature dealt damage by ~ dies this turn put a +1/+1 counter on ~.
When ~ dies, return it to the battlefield transformed under your control with a number of additional loyalty counters equal to the number of +1/+1 counters on ~.
4/3
//
Sorin, Awakened Vampire (color indicator R/B)
[-2]: Put a 2/2 black Vampire creature token with intimidate onto the battlefield
[-3]: Destroy target creature, Put loyalty counters on ~ equal to that creature's toughness.
[-10]: Gain control of all creatures on the battlefield, they become vampires in addition to their other types.
2
The painful transformation awakens the thirst within him. A thirst he has yet learned to control.
Forgemaster Gryz1RR
Legendary Creature - Human artificer
Equipments you control gain indestructible. RRt sacrifice an artifact: You may put an Equipment card from your hand or graveyard onto the battlefield.
2/3 Though Mirrodin has fallen some still fight back against they Phyrexians.
Next: A Phyrexianized version of a Mirran legendary.
I've also seen lists that run a Bayou/Arbor split so that they can cast both halves of Cabal Therapy in addition to the green anti-hate cards. But Bayou is fairly expensive so its not as budget friendly as just Arbors.
Land Grant to act as additional copies of Arbor in case its not in your opening hand and you need it, fast. Silence to kill Leylines and RIPs immediately after playing Arbor rather than risk it getting wasted/bolted/swords away before you can cast nature's claim.
Sickening Shoal pitching Phantasmagorian is pretty much the only way to remove her once she its play.
Surgical Extraction and Faerie Macabre are probably your best options. You can also run Leyline of the Voids if it gets to be a big enough problem.
Dredge can certainly combo out very quickly, but I find I win a lot of games (even with Manaless Dredge) through being one of the best decks at grinding. I generate a lot more card advantage than my opponents through dredging. Because I make zombie tokens I get more out of trades than my opponents do. And I can shred their hand with Cabal Therapy. Dredge is a very powerful attrition deck. Its not the main plan of the deck, but it certainly can play the attrition game well. Swinging in for a couple of points of damage each turn, you win most races. I've out paced a Belcher decks that Emptied on turn 1 because my zombies are better than their goblins and I win the topdeck war.
Legendary Creature - Saytr Shaman
Haste, Trample
RG: ~ gets +1/+1 until the end of the turn, exile the top card of your library. Until the end of your next turn, you may play that card.
Whenever ~ deals combat damage to a player you may exile the top card of your library. Until the end of your next turn, you may play that card.
3/4
Next: a legendary horror
Legendary Creature - Avatar
You have no maximum hand size
Players do not lose the game from drawing cards while there are no cards left in their decks.
3UUUt: Each other player discards his or her hand, then all players draws cards equal to the greatest number of cards a player discarded this way.
2/2
Next: A legendary Bear (the creature type)
3 major versions:
Fearless = no anti-hate
Green = Dryad Arbor + Nature's Claim + Reverent Silence and uses Griselbrand over Baltrusade Spy
Blue = Force of Will + Distrupting Shoal and uses Whirlpool Rider over Baltrusade Spy
LED Dredge: Weaker vs counter magic. Able to Dredge faster and its easier to get a dredger in the graveyard. Easier to cast anti-hate in post-board games and can use loot effects to dig for them. Being able to cast both halves of Cabal Therapy is much better than only flashing it back. Can generate large amounts of card advantage on the first turn and has more explosive opening hands than Manaless. While not a good option, can hard cast the creatures in the deck, but is still useful.
In short, Manaless is better vs countermagic, LED Dredge is better vs graveyard hate.
Legendary Creature Squid
Islandwalk
When ~ enters the battlefield tap all other permanents.
Other permanents do not untap during their controller's untap step for as long as ~ is on the battlefield.
Discard a card: you may tap or untap target permanent. Any player may activate this ability, but only during their untap step.
9/9
Next: The person featured on and quoted in Last Word
Legendary land creature - Swamp Dryad
~ is black
Swamps you control have "Bt, pay 2 life: draw 1 card"
2Bt: target creature gets -X/-X where X is the number of Swamps you control.
2/2
Next: A teacher or philosopher.
Every other round my deck performed well. The only other game I can remember bricking was a game 3 vs Omni-tell. I was dredging but didn't hit Ichorids and only hit a single Bridge but between occasional Narcos and Therapies combined with my opponent bricking hard as well I was able to stretch the game out until I finally hit a LED and with a flashbacked looting managed to end the grindfest.
From my experience, I wind up mulliganing to death around 1/10 matches. I run a fairly stock Quadlazer list, I just have 3 Breakthrough & 3 Putrid Imp rather than the full 4 so I can have a DR and Iona in the main. Everything else is a 4 of.
Its really rare that I ship a hand. I'll pretty much only do it if I have absolutely no way to discard a dredger, even if that way is to timewalk myself so I can discard to max handsize (though that I only do if its against a slower deck or if my opponent mulled down a lot). I'll keep 0 dredger hands if I have some loot effects.
Legendary Creature - Human Advisor
Vigilance
Whenever a creature dealt damage by ~ dies this turn put a +1/+1 counter on ~.
When ~ dies, return it to the battlefield transformed under your control with a number of additional loyalty counters equal to the number of +1/+1 counters on ~.
4/3
//
Sorin, Awakened Vampire (color indicator R/B)
[-2]: Put a 2/2 black Vampire creature token with intimidate onto the battlefield
[-3]: Destroy target creature, Put loyalty counters on ~ equal to that creature's toughness.
[-10]: Gain control of all creatures on the battlefield, they become vampires in addition to their other types.
2
The painful transformation awakens the thirst within him. A thirst he has yet learned to control.
Next: A commander who still wants to be tucked.
Legendary Creature - Human artificer
Equipments you control gain indestructible.
RRt sacrifice an artifact: You may put an Equipment card from your hand or graveyard onto the battlefield.
2/3
Though Mirrodin has fallen some still fight back against they Phyrexians.
Next: A Phyrexianized version of a Mirran legendary.
Creature - Wall
Defender
~ can block any number of creatures
Creatures your opponents control attack each turn if able.
0/7