In order to give you a snapshot feel for how Standard is about change with rotation, I have fairly exhaustively outlined the 20 biggest changes that will occur when Battle for Zendikar is released in two weeks. Also attached at the end is a list of every playable card leaving, staying, or entering Standard that was not mentioned in the Top 20 Changes.

Note that I am not comparing post-rotation Standard to Standard a year ago. For example, Thassa, God of the Sea was a major player in Standard a year ago but currently is not and is therefore not listed among the 20 biggest changes to Standard, despite only now rotating. Similarly, Esper Dragons is a big deck now and will remain a big deck post-rotation. Since this article is focused on changes and Esper's positioning does not change, it is therefore likewise not listed among the 20 biggest changes to Standard.

In reverse order, starting with the 20th biggest change...

#20 GW Hardened Scales Gains a Champion
GW Hardened Scales improves. It only loses Gods Willing, Temple of Plenty, and Mana Confluence. Gods Willing can be replaced by Feat of Resistance. The mana also improves by adding Canopy Vista, Wooded Foothills, and Flooded Strand. It also gains Undergrowth Champion as a premier three-drop to go alongside Managorger Hydra. With the power level of Standard decreasing with rotation and this deck improving, one can't help but assume it will rise in popularity.

#19 The New Ingest Mechanic will take Time to Process
Ingest is primarily a UB mechanic where early ingest creatures exile cards from the top of the opponent's library and then midgame creatures and spells generate powerful effects by utilizing the exiled cards as a resource. Mist Intruder, Fathom Feeder, and Benthic Infiltrator are hard to block, which makes them semi-reliable ways to trigger ingest for Wasteland Strangler and Ulamog's Nullifier. Sire of Stagnation is the high end for the UB mini Eldrazi. It's unclear how competitive this mechanic will prove to be, but it's likely somewhere between Warriors and Heroic.

#18 Constellation Heads for the Stars
Doomwake Giant, Eidolon of Blossoms, and several key enchantments are leaving Standard, most notably Courser of Kruphix and Banishing Light. Abzan Constellation had a few weekends where it performed very well, though it was mostly a Tier 2 strategy. It will no longer exist next month.

#17 UR Mill Becomes Radiant
UR Cuneo Mill survives. It only loses Temple of Epiphany and Anger of the Gods. It can fairly easily replace Anger with Radiant Flames and can replace Temple with Mystic Monastery and can add Flooded Strands and a Prairie Stream to have nine sources of white for times when you need to deal the full three damage with Radiant Flames. The deck remains almost entirely intact so, like Hardened Scales, I expect its stock to rise.

#16 Crack, Fetch, Trigger Landfall!
The aggressive landfall creatures are red and green and their stats are competitively costed. The base power of the creatures is higher than those in original Zendikar (Plated Geopede, Steppe Lynx) but they get a smaller bonus from landfall triggers (+1/+1 instead of +2/+2). With fetch lands in the format, they can hit quite hard. And without Fleecemane Lion around anymore, Naya is in the market for exactly these types of creatures. Scythe Leopard, Snapping Gnarlid, and Makindi Siderunner are the best ones, but Akoum Firebird, Akoum Stonewalker, and Valakut Predator may also show up.

#15 Black Slows its Roll
Black loses Gnarled Scarhide, Tormented Hero, Herald of Torment, and Mogis's Marauder. While it still has Bloodsoaked Champion, a dedicated Black Aggro deck will no longer look the way it did pre-rotation. That deck has kind of fallen out of favor anyway, but it will now be forced to move up the curve a bit, perhaps playing Gurmag Angler, Erebos's Titan, Grim Haruspex, Liliana, Heretical Healer, Nantuko Husk, or Sidisi, Undead Vizier. Black gains Carrier Thrull, Drana, Liberator of Malakir, and Smothering Abomination, and there may prove to be a synergistic vampire tribal deck centered around life gain bonuses and Drain Life triggers. Either way, it will no longer be all-in one-drop two-power aggro.

#14 Four New Card Advantage Engines
Jace's Ingenuity, Whip of Erebos, and Chord of Calling are leaving and are being replaced by Ugin's Insight, Painful Truths, Bring to Light, and March from the Tomb. Ugin's Insight can be more powerful than a Dig Through Time late, yet is sorcery speed. Bring to Light is also a sorcery, though its versatility is through the roof, being good in nearly every scenario in which a five-mana sorcery speed play is good. Painful Truths will likely see play in various multicolor decks, at least out of the sideboard for attrition matchups. March from the Tomb will act as a second copy of Rally the Ancestors if Allies prove good enough. Of course all these card advantage engines still have to compete with the ones that are sticking around: Outpost Siege, Dig Through Time, Dragonlord's Prerogative, Treasure Cruise, Mastery of the Unseen, Read the Bones, Day's Undoing, Collected Company, Evolutionary Leap, Nissa's Revelation (Eldrazi), See the Unwritten, and Jeskai Ascendancy.

#13 What's the Ordeal with Heroic Rotating Out?
Battlewise Hoplite, Hero of Iroas, and Favored Hoplite are leaving and they are taking with them nearly every other card in the UWx Heroic deck: Aqueous Form, Ordeal of Thassa, Ajani's Presence, Gods Willing, and Ordeal of Heliod. We get to keep Stratus Walk, but that's not going to cut it. This is one of a handful of decks that was heavily reliant on a block-specific theme and cannot survive rotation.

#12 White Learns Some New Tricks
White loses Banishing Light, Glare of Heresy, Devouring Light, Last Breath, Reprisal, Fated Retribution, and Mass Calcify. It keeps Valorous Stance, Celestial Flare, Hallowed Moonlight, Hidden Dragonslayer, Pacifism, Radiant Purge, Silkwrap, Surge of Righteousness, Suspension Field, Swift Reckoning, Tragic Arrogance, and End Hostilities. It gains Stasis Snare, Planar Outburst, Gideon's Reproach, and Quarantine Field. Although Glare of Heresy saw the most play among these losses, Banishing Light will be missed the most as it could answer noncreature permanents. Quarantine Field is the replacement and can be better in the late game but is more difficult to utilize in an aggressive deck. Stasis Snare has flash and Planar Outburst has awaken, so I expect each of those cards to see play alongside Valorous Stance, Tragic Arrogance, and whatever other specific answers the metagame calls for.

#11 Blue Awakens to a New Counterspell
Blue loses Dissipate, Dissolve, and Nullify, but gains Scatter to the Winds. Silumgar's Scorn has already replaced Nullify while Negate and Disdainful Stroke are the better sideboard options. Clash of Wills and Stubborn Denial are also options in decks that want a less color-intensive counter. Scatter to the Winds is better late game than Dissolve but worse early. This is a fair tradeoff as long as the deck is running Silumgar's Scorn as its early counter. Blue's countermagic remains fairly strong.

#10 Red Loses Stormbreath, Rabblemaster, and Eidolon
Red loses three of its best creatures: Eidolon of the Great Revel, Goblin Rabblemaster, and Stormbreath Dragon. None of these have great replacements either. Foundry Street Denizen and Firedrinker Satyr are fairly easily replaced by Monastery Swiftspear, Zurgo Bellstriker, and Lightning Berserker, and Abbot of Keral Keep is still a thing. Likely some of the creatures that will have to step up in the absence of these three superstars will be Goblin Heelcutter, Hordeling Outburst, Chandra, Fire of Kaladesh, Thunderbreak Regent, Pia and Kiran Nalaar, and Ashcloud Phoenix. Or, what is more likely, red will have to venture into a second or third color in order to gain access to green landfall creatures, Mantis Rider, or something along those lines. Eidolon triggers have probably been forgotten more times than the triggers for any other card, so I'm sure a lot of players are happy to see that one exit. As for me, I could not be happier about the rotation of Stormbreath Dragon. Joke's on WotC: I still made Platinum despite having to fight through two years of a dragon with protection from Craig Wescoe!

#9 The Hills are Alive with the Sound of Music
Lumbering Falls and Shambling Vent are lands that come to life and are thus big additions to Standard! With many of the best one-drops rotating, as well as the ten temples, they make for a great turn one play. The only problem is that Battle lands incentivize starting with basic lands on the first two turns so that they can enter untapped starting on the third turn. This means that, depending on your curve, sometimes you'll want to play the creature land on turn one while other times you'll want to wait until later in the game. Either way, these lands are great! And they are also good targets for awaken counters if you feel like putting all your vegetables in one basket.

#8 White Devotion Loses its King and its Land
White Devotion loses Brimaz, King of Oreskos, Soldier of the Pantheon, and Nykthos, Shrine to Nyx. Devotion per se will no longer exist, but this does not necessarily spell the death of white weenie. It may, however, have to dip into another color for assistance. White keeps Kytheon, Hero of Akros, Anafenza, Kin-Tree Spirit, Arashin Cleric, Consul's Lieutenant, Knight of the White Orchid, Seeker of the Way, Vryn Wingmare, Monastery Mentor, Archangel of Tithes, Wingmate Roc, and Secure the Wastes. It also gains Felidar Cub for utility, Emeria Shepherd if it wants to go bigger, and Unified Front if it wants to venture out into several colors. Even though Brimaz is leaving, I doubt Sam Black and I are done casting Wingmate Roc.

#7 Red Loses its Fire
Red loses Stoke the Flames, Lightning Strike, Anger of the Gods, Searing Blood, Shrapnel Blast, Magma Spray, and Magma Jet. It gains Radiant Flames to replace Anger of the Gods and it gains Touch of the Void if it is desperate to exile something. Processor Assault and Rolling Thunder are also marginally playable, but nothing comes close to replacing Stoke the Flames or Lightning Strike. Red does get to keep some powerful burn spells though: Roast, Draconic Roar, Exquisite Firecraft, Wild Slash, Arc Lightning, Crater's Claws, Fiery Impulse, Rending Volley, Twin Bolt, and Collateral Damage. The biggest change is that red burn gets weaker overall and that control decks looking to gain a cheap sweeper effect will have to be three or more colors since Anger of the Gods is replaced by Radiant Flames. As a result, cards like Deathmist Raptor have less natural enemies and may consequently flourish.

#6 Black Disruption Takes a Beating
Black loses Thoughtseize, Hero's Downfall, Bile Blight, Drown in Sorrow, Pharika's Cure, and Silence the Believers. Hero's Downfall only gets slightly downgraded by Ruinous Path while Thoughtseize gets significantly downgraded to Transgress the Mind. Duress and Despise are still legal though too. Drown in Sorrow and Bile Blight do not have adequate replacements, though Languish and Crux of Fate are still around to clean things up in the midgame. Murderous Cut is still great and Ultimate Price is playable but likely loses a lot of stock with the addition of colorless creatures and the improved mana to support multicolor creatures. Black still has great sacrifice effects though: Fleshbag Marauder, Merciless Executioner, Foul-Tongue Invocation, and Self-Inflicted Wound. And Infinite Obliteration could be a good answer to Eldrazi while Virulent Plague can take care of Eldrazi Scion tokens. Overall, however, Black disruption really got hit hard by rotation.

#5 Elspeth, Ajani, and Xenagos Planeswalkers Take a Hike
Chandra, Pyromaster, Jace, the Living Guildpact, Ajani Steadfast, Elspeth, Sun's Champion, Liliana Vess, Nissa, Worldwaker, Ashiok, Nightmare Weaver, Garruk, Apex Predator, Xenagos, the Reveler, Ajani, Mentor of Heroes, and Kiora, the Crashing Wave are gone. Sarkhan, the Dragonspeaker, Ugin, the Spirit Dragon, Sarkhan Unbroken, Narset Transcendent, and Sorin, Solemn Visitor stay. Gideon, Ally of Zendikar, Ob Nixilis Reignited, and Kiora, Master of the Depths enter. Abzan will have to take on a slightly different form without Elspeth, but as long as Siege Rhino is around, Abzan will continue to be viable. The new Gideon is pretty exciting and I'm looking forward to acquiring my playset.

#4 Green Devotion Rotates the Elf Outta Standard
Green Devotion, much like Heroic, got completely annihilated! In addition to losing Xenagos, it lost Elvish Mystic, Sylvan Caryatid, Courser of Kruphix, Polukranos, World Eater, Genesis Hydra, Hornet Queen, Nylea's Disciple, Arbor Colossus, and Nykthos, Shrine to Nyx. Green as a color will survive, but it will have to take on a new direction. Deathmist Raptor, Den Protector, and Whisperwood Elemental still constitute a very powerful shell despite losing Elvish Mystic. It gains Beastcaller Savant to go alongside Shaman of Forgotten Ways in a creature-heavy build. Whisperer of the Wilds, Nissa, Vastwood Seer, and Rattleclaw Mystic could also work to replace Sylvan Caryatid. Avatar of the Resolute, Gaea's Revenge, Heir of the Wilds, Hooting Mandrills, Surrak, the Hunt Caller, Woodland Bellower, and Elvish Visionary also survive rotation while Blisterpod, Greenwarden of Murasa, Jaddi Offshoot, and Woodland Wanderer now exist. Green will survive, but losing Elvish Mystic will completely change the game plan.

#3 Battle Lands Trying to Make Fetch Happen
Mana Confluence and the 10 temples are gone, but the three powerful fixing cycles remain - painlands, fetchlands, and Khans trilands - while a new Rare Battle land cycle is added. The battlelands, in conjunction with fetchlands, make the mana in Standard overall much better than it was with Mana Confluence and the 10 temples. I expect several decks to run approximately 12 fetchlands so they can fetch basics (or play basics from hand) the first two turns of the game and then start fetching battlelands untapped for the next few turns. The mana involves minimal pain and is fairly smooth, even for three-color decks. Subsequently I expect the use of painlands to decline.

#2 Gold Rises in Value
Given the improved color fixing in the format, I expect gold cards to rise in stock. It really only gained a few marginally exciting multicolor cards (Brutal Expulsion, Roil Spout, and Noyan Dar, Roil Shaper), but the mana makes combinations of existing cards possible that weren't before. And with Nykthos gone, there is no longer much incentive to stay in a single color. Some of the premier spells in the format are multicolor: Ojutai's Command, Utter End, Kolaghan's Command, Atarka's Command, Dromoka's Command, Abzan Charm, Crackling Doom, Jeskai Charm, and Sultai Charm. Likewise are some of the best creatures in the format: Soulfire Grand Master, Tasigur, the Golden Fang, Warden of the First Tree,, Dragonlord Ojutai, Dragonlord Silumgar, Silumgar, the Drifting Death, Kolaghan, the Storm's Fury, Rakshasa Deathdealer, Dragonlord Atarka, Dragonlord Dromoka, Siege Rhino, Anafenza, the Foremost, Butcher of the Horde, Mantis Rider, Savage Knuckleblade, and Sidisi, Brood Tyrant. I expect all kinds of multicolor combinations to crop up.

The biggest change is...

#1 The Return of the Eldrazi!
Hangarback Walker is no longer in a class of its own among colorless creatures! While the mini Eldrazi processors and drones are technically Eldrazi, the really impactful ones are the skyscrapers of the format. Hedron Archive, Sanctum of Ugin, Shrine of the Forsaken Gods, and likely green mana acceleration will enable the monsters. Conduit of Ruin and Oblivion Sower are the intermediate plays while Void Winnower, Desolation Twin, and Ulamog, the Ceaseless Hunger are the big payoff cards. Titan's Presence is the Draconic Roar of Eldrazi. I also expect Nissa's Revelation and See the Unwritten to find homes in Eldrazi Green.

Everything Else

The following is a fairly exhaustive list of cards that are leaving, staying, or entering at Rotation that have not already been mentioned in the article:

Leaving
Black:
Gray Merchant of Asphodel, Nighthowler, Dark Betrayal, Erebos, God of the Dead, Master of the Feasts, Pain Seer, Sign in Blood, Soul of Innistrad, Stain the Mind, Ulcerate, Waste Not
Blue: Ensoul Artifact, Retraction Helix, Chief Engineer, Daring Thief, Dictate of Kruphix, Gainsay, Interpret the Signs, Jorubai Murk Lurker, Divination, Swan Song, Aetherspouts, Prognostic Sphinx, Master of Waves, Thassa, God of the Sea, Bident of Thassa, Omenspeaker
Green: Satyr Wayfinder, Hornet Nest, Boon Satyr, Reclamation Sage, Hunt the Hunter, Setessan Tactics, Unravel the Aether, Back to Nature, Reclamation Sage, Archetype of Endurance, Aspect of Hydra, Bow of Nylea, Commune with the Gods, Gather Courage, Mistcutter Hydra, Naturalize, Nylea, God of the Hunt,