Most significant 'new' set on legacy?

[Jenni]

I'm kinda curious about what recent sets (say, since Alara block) have had the biggest impact on legacy?
They've all added something to legacy, but I'm having trouble making up my mind which has had the largest impact. Was it avacyn's miracles? Zendikars new fetches? Phyrexia's equipments? worldwakes jace and mystic?
What do you lot think?

Personally, I think Jace and stoneforge - both from worldwake - might have made the biggest impact.

[John Cox]

Zendikar had a host of playables, from Spell Pierce and enemy fetches to Iona, Shield of Emeria, Mindbreak Trap, and Bloodghast.
I think it wins the prize.

[troopatroop]

Delver and Snapcaster

[Esper3k]

Zendikar and Alara block were both huge sets for Legacy. Of the two, I'd say Zendikar was still the bigger set although it's close.

[Koby]

Rise of Eldrazi had the most impact. How do I ascertain this?

It got Survival of the Fittest banned.
It still roars waves whenever you get Torn.
Inquisition of Kozilek.
Forked Bolt your mana dorks.
etc

[Greenpoe]

Innistad had a huge impact on Legacy: Delver of Secrets and Snapcaster Mage are the big ones, plus Geist of Taft Saint, Liliana of the Veil, and for combo, Past in Flames. Oh, and Labratory Maniac has seen some play in Doomsday.

[Fizzeler]

Alara Block followed by Scars

Alara had a great impact on Legacy:
Knight Of The Reliquary
Path To Exile
Noble Hierarch
Progenitus
Elspeth, Knight Errant
Cascade mechanic
Master Of Etherium
Ethersworn Canonist
Conflux
Wild Nacatl
Qasali Pridemage
Sphinx Of The Steelwind

I am sure there are more (I have seen some Knight Of New Alara decks that float around), but it has had a great impact on Legacy

[John Cox]

Rise of Eldrazi had the most impact. How do I ascertain this?

It got Survival of the Fittest banned.
It still roars waves whenever you get Torn.
Inquisition of Kozilek.
Forked Bolt your mana dorks.
etc

Yeah LOL technically that set has put two cards within ban range.

[menace13]

I feel Ever since Mirrodin is where the change happened. Alara probably has the most cards for Legacy in any block from Mirrodin to now.I would rate them in order;
Alara
Scars
Zendikar
Innistrad
Lorwyn
Mirrodin
Time Spiral
Kamigawa
Coldsnap

[Barook]

New Phyrexia had quite some cards as well:

Batterskull
Dismember
Elesh Norn, Grand Cenobite
Gitaxian Probe
Gut Shot
Jin-Gitaxias, Core Augur
Mental Misstep
Phyrexian Metamorph
Surgical Extraction

To name just important ones, while there are some other cards as well.

[Koby]

I think Alpha had the biggest impact on Legacy, if we look back that far.

Swords to Plowshares
Lightning Bolt
Counterspell
Dark Ritual
basic lands

Half the Ban list appear from Alpha.
Clearly, it's overpowered.

[joemauer]

Homelands would have been the most broken set if they didn't print Apocalypse Chime to keep that broken set in check.

[lordofthepit]

Easily New Phyrexia.

Mental Misstep was the most played card during its run in Legacy and it's the only "new" card to be banned from Legacy. In fact, you'll have to go back to 2004 with Darksteel (Skullclamp) to see the next "newest" banned card.

Mental Misstep saw more play than Brainstorm. Brainstorm sees far more play than any two or three new cards put together. This includes the likes of Delver of Secrets and Snapcaster Mage. I'd guess that Mental Misstep by itself sees more Legacy play in a given tournament than the entirety of Innistrad. (According to TCDecks for August: Brainstorm = 940; Delver = 336; Snapcaster Mage not in top 20, so fewer than 284).

If that weren't enough, consider that Surgical Extraction has been the most played sideboard card and the most played black card for just about every month since it's been released. Batterskull was found in every viable control deck since its release (until Avacyn Restored brought some goodies that allowed control decks to go in a different direction).

Add to that the likes of Elesh Norn, Jin-Gitaxias, Gitaxian Probe, Phyrexian Metamorph, and Dismember, all of which see decent play. In addition, Procelain Legionnaire, Noxious Revival, Spellskite, Vault Skirge, Gut Shot, Beast Within, Birthing Pod, and Torpor Orb have all seen occasional play, even if relatively little.

[UnsungHero]

Time Spiral Block had some nice stuff.

Bridge From Below
Nacromeba
Dread Return
=All 3 made Dredge what it is.
Tarmogoyf= raised the bar for low cost/high power creature, one of the most splashed creatures ever
Tombstalker=Very popular card for the old TA style decks
Serra Avenger/Mangara=Popular DnT Cards
Tolaria West=Lands Staple
Academy Ruins=Lands Staple,Frequently seen land card for blade decks
Empty The Warrens=Alternate Win Con For Storm

Not saying that TS block is the definitive game changing block, but it pretty much made the dredge archetype playable. And Goyf is still a great card in pretty much every format.

[Jacemindbreak]

I think Alpha had the biggest impact on Legacy, if we look back that far.

Swords to Plowshares
Lightning Bolt
Counterspell
Dark Ritual
basic lands

Half the Ban list appear from Alpha.
Clearly, it's overpowered.

I would say beta because you get an extra dual

[tonedown]

I would say beta because you get an extra dual

And a good one at that.

[LOurs]

By far Alara to me
knoght of reliquary
noble
quasali
nacatl
canonist
path to exile
elspeth
adnauseam
relic of progenitus
sigil of the empty throne
progenitus
pulse
Akroma's sphinx
tezzeret
thopter foundry
elvish visionnary
Master of etherium
conflux
…


the set defined a new Bant shell, provided a very powerful new storm engine, some good hates, some niche but useful cards, exalt & cascade mechanics (even if not that played in legacy, but they still appear sometime though).
Definitly the most impactful recent set to me because it feeded each strategy (combo / control / aggro) at almost the same level of potence, and really defined a new environment. As well there was really good cards in zendikar, mirrodin and innistrad, but still a bit less than alara did to me.

[phonics]

Well alara was a block so it was three sets not one.

[TheInfamousBearAssassin]

Koby's argument is pretty compelling for RotE, although I think if we go by weight-per-card it has to be Conflux. For a small set you got these heavy hitters:

Noble Hierarch
Knight of the Reliquary
Path to Exile
Progenitus

+ the middling:

Hellspark Elemental
Inkwell Leviathan
Conflux
Sigil of the Empty Throne

And the borderline:

Banefire
Volcanic Fallout
Magister Sphinx
Parasitic Strix

[Koby]

Yay! Math and data!!
Top 20 played cards according to TCdecks (August):
1 Brainstorm 940 (IA)
2 Force of Will 876 (AL)
3 Wasteland 782 (TE)
4 Swords to Plowshares 642 (A)
5 Ponder 584 (LOR)
6 Spell Pierce 568 (ZEN)
7 Misty Rainforest 511 (ZEN)
8 Scalding Tarn 475 (ZEN)
9 Daze 434 (NE)
10 Lightning Bolt 423 (A)
11 Surgical Extraction 409 (NPH)
12 Flooded Strand 402 (ONS)
13 Volcanic Island 397 (B)
14 Polluted Delta 340 (ONS)
15 Delver of Secrets 336 (INN)
16 Submerge 314 (NE)
17 Stoneforge Mystic 301 (WWK)
18 Tropical Island 300 (A)
19 Tarmogoyf 291 (FS)
20 Tundra 284 (A)

Discounting the fetchlands as a cross-set phenomenon, since the highest played ones are Blue fetching anyway.

We see Alpha/Beta dual lands, cantrips, Force of Will and Wasteland.

Closer inspection of the top 20 reveals:

Row Labels Sum of #
A 1649
ZEN 986
IA 940
AL 876
WWK 869
TE 782
NE 748
ONS 742
LOR 584
NPH 409
B 397
INN 336
FS 291

If we eliminate fetchlands, this changes to become:
Row Labels Sum of #
A 1649
IA 940
AL 876
WWK 869
TE 782
NE 748
LOR 584
NPH 409
B 397
INN 336
FS 291

Suck it, told you it's Alpha.