and
Mega Aggron and Sap Sipper Azumarill
Aggron-Mega @ Aggronite
Ability: Filter
EVs: 252 HP / 16 Def / 240 SpD
Impish Nature
- Earthquake/Rock Slide/Dragon Tail
- Thunder Wave
- Heavy Slam/Iron Head
- Avalanche/Earthquake/Fire Punch
Azumarill @ Leftovers
Ability: Sap Sipper
EVs: 252 HP / 252 Def / 4 Spe
OR 252 HP / 114 Def / 138 SpDef / 4 Spe
Bold Nature
- Toxic
- Scald
- Encore/Sleep Talk/Knock Off
- Rest/Perish Song
Basics: Tank Mega Aggron and Sap Sipper Azumarill form a strong,
flexible status spreading core that
checks/counters many common meta threats such as Weavile (countered by either), the
Lati twins (countered by either),
Keldeo (countered by Azumarill),
Bisharp (checked/countered by both depending on your choice of moves),
both Zards (Zard X checked by Mega Aggron and countered by Azumarill, Zard Y soft countered by Azumarill),
Mega Latias (countered by either if BoltBeam, countered by either if no Refresh),
Breloom (countered by Azumarill, can be checked in an emergency by Aggron assuming something else is already asleep),
Clefable (countered by Aggron, unless Max SpA Modest LO Fire Blast Clefable hits you on the switch),
TG Manaphy (if you play it right, Azumarill can counter it, but at the very least it's a check),
AV/Band/BD Azumarill (checked/countered by Aggron in all cases),
Serperior (checked by Aggron, hard countered by Azumarill),
Volcarona (checked by Aggron, countered by Azumarill),
Mega Altaria (countered in most cases by Mega Aggron),
Tyranitar (any version without special Fire coverage tends to lose to Aggron, and choiced variants locked into Crunch/Pursuit get beaten by Azumarill or Aggron),
Kyurem-Black (checked by Mega Aggron), and others.
Set Details
Mega Aggron: The Mega Aggron EVs are pretty standard for Tank Mega Aggron. Patch up your weaker SpDef side and still have
550 points of Defense. You can eat a Mega Medicham's Adamant HJK after rocks and never be OHKO'd (thanks to Filter). That's disgusting. Move slots are very customizable, as Mega Aggron actually has a ton of options.
Thunder Wave is the preferred status move over
Toxic because while bulky grounds do like to switch in against you, the bigger threat is set up sweepers like Zard X and Volcarona, who both despise being Thunder-Waved (even if the latter carries Lum, because you can just Twave again and survive an unboosted Fire Blast). No rocks because one of the best partners to this core (full SpDef Hippo) loves to run rocks, and you really like the extra free moveslot.
Heavy Slam versus Iron Head: Heavy Slam nails things like Azumarill, Clefable, Gardevoir, Tornadus, and so on much much harder (OHKOing standard Clefable 50% of the time versus doing below 70% with Iron Head) but loses out on things like Tyranitar, Mamoswine, and so on, so choose what your team wants to hit (IMO Heavy Slam is most often better, because Tyranitar really does not generally want to stay in on Mega Aggron unless it has fire coverage, and even then, unless it's fully invested, you do tons back before dropping or winning).
Avalanche is almost mandatory as it lets you nail important things like the Lati twins (you cleanly 2HKO the standard defensive Mega Latias set with Avalanche), the genies, Garchomp, and anything that does not like Ice coverage.
Fire Punch lets you beat Mega Scizor and regular Scizor, which can otherwise set up on you, while
Earthquake gives you excellent neutral coverage and lets you check Mega Metagross and Tyranitars a lot better (especially if you're running Iron Head over Heavy Slam), as well as hitting Raikou and Mega Manectric on the switch.
Rock Slide lets you beat on Talonflame and Volcarona on the switch which is great since they're common switch-ins.
Dragon Tail is a pretty good choice as well, since you can shuffle things quite nicely due to your massive bulk.
Azumarill: Two EV options, obviously customizable. The first is focused on Def, and lets you counter the Lati twins (LO Psyshock is a 3HKO at best) and other physical attackers much better, while the latter is more SpDef oriented and lets you wall/beat TG Manaphy and Keldeo a lot easier. Or you can make your own EV spread, just figure out what works best for your team. With this set, if you can, try and conceal that you're Sap Sipper, as that makes your job of beating things like Volcarona and Zard Y much easier since they'll waste a turn using their grass coverage on you, while you nail them with Encore or Toxic. Speaking of move slots, there's a lot of options here too.
Toxic is mandatory, because it lets you nail things like Serperior, Volcarona, TG Manaphy, Zard X and other set up sweepers who are either unaffected by Scald burns or can't be burned.
Scald is basically mandatory as well since you don't want to be Taunt fodder, and Scald burns let you beat things like Breloom and Scizor that much easier.
Knock Off is a nice option since removing items is always cool, but I prefer
Encore for the ability to lock things like Volcarona/Breloom/Serperior into their grass moves and then to either hit them or the inevitable switch in with a Toxic. It also makes you less vulnerable to strong set-up sweepers which is always good.
Sleep Talk is also really good when paired with
Rest, which gives you semi-reliable recovery (plus, people don't expect it so you can often nail things with Scald or Toxic on the switch).
Perish Song is actually quite viable, since it lets you beat things that you can't otherwise like Suicune, CM Manaphy, CroBro, and Curse Gastrodon. Choose based on what you need this core to check/counter, and go from there.
Core Weaknesses and How to Patch Them
Electric types make this core very very sad. Mega Manectric, Raikou, Thundurus-T, and Rotom-Wash are all very strong against this core. Mega Aggron can check Thundurus-T and MegaMan and Raikou with Avalanche and EQ respectively, but you lose the 1v1s most of the time.
Certain setup sweepers like Mega Scizor can make this core very sad if you don't carry Fire Punch, and SD/Lum Garchomp can also run the train on this core if it gets to set up freely (although it must be careful of being locked into SD with Azumarill and +2 EQ maxes out at 72% against Aggron which can OHKO back with Avalanche). CroCune, CM Manaphy, CroBro, and Curse Gastrodon have a field day with this core if you don't pack Perish Song (and even then you can't do much back with just this core unless you lock them into something with Encore).
Strong special attackers with coverage like Mega Alakazam also blast through this core if its members are somewhat weakened.
One of the best partners to this core as a result is Max SpDef Hippowdon.
Hippowdon @ Leftovers
Ability: Sand Stream
EVs: 252 HP / 252 SpDef / 4 Def
Careful Nature
- Stealth Rock
- Stone Edge
- Earthquake
- Slack Off
This set, with max SpDef, lets you counter MegaMan, Thundurus-T, Tornadus-T, and Raikou, with much more room for error when compared to the standard mixed Hippo spread. Plus, it gets up Rocks (freeing up a valuable slot on Aggron!) and gives some nice chip damage for Sand which really helps the core beat what they're supposed to beat (often times there's a 50% chance of Aggron OHKOing something, which Sand damage guarantees then).
Rotom-W still dumpsters you for instance, as do the special sweepers mentioned earlier, but that's easily accountable for in team building.