I wanted to build with Victreebel, and my initial thought was a standard core with an extra steel to target don/ogre/hooh via spikes+mash and via having a 'free' explosion. Steels, the other common problem Victreebel struggles with, are fended off with fire moves on everything and then bypassed lategame with hpfire Victreebel. I wanted extra resilience vs Latios, so I chose Blissey as its check over Snorlax; since Victreebel pushes past Latios lategame my gameplan before then is to force it out reliably rather than try to make progress on it. Thus, the first pass was Groudon / Latios / Blissey / Metagross / Forretress / Victreebel.
I went through a number of versions of the team after this; I noticed trouble vs firelax and hooh, so I swapped Forretress for Regirock; I found I had trouble vs subcm stuff so I put Registeel over Metagross, which via being another Latios check let me drop Blissey for another boom in Snorlax.
The final (or at least current) version of the team is
Groudon @ Leftovers
Ability: Drought
Shiny: Yes
EVs: 252 HP / 56 Def / 120 SpD / 80 Spe
Impish Nature
- Bulk Up
- Earthquake
- Rock Slide
- Overheat
Groudon of course brings Victreebel's sun. Rather than trying to keep sun up as aggressively as possible, I usually conserve Groudon earlygame while I try to get a boom off on opposing Kyogre. Besides Drought, Groudon checks Ray and Ho-Oh, opposing Groudon, opposing Snorlax, and DeoA. A defensive spread lets it take these threats on as effectively as possible, with enough speed to reliably outspeed opposing Groudon (and possibly finish off Kyogre). Since its function on this team is primarily defensive, HPGhost isn't really necessary - it forces out what it wants to force out better with slide. Ho-Oh may stay in and fish for a burn, but even if it outspeeds and does burn getting a slide off vs hooh will usually advance your gameplan significantly.
Bulk Up is to match up better defensively vs don and lax. Slide is important to properly hit Ho-Oh in particular and Ray. Overheat is essential to prevent spikes from Forretress, as well as eliminate Metagross and Forretress before they can blow you up. I forget what the EVs do.
Latios @ Soul Dew
Ability: Levitate
Shiny: Yes
EVs: 76 HP / 252 SpA / 180 Spe
Timid Nature
IVs: 2 Atk / 30 SpA / 30 Spe
- Thunder
- Ice Beam
- Hidden Power [Fire]
- Recover
Latios checks Groudon and Kyogre. HPFire eliminates Metagross in Sun and Forretress, preventing Spikes, removing boom resists, and forcing in Snorlax to allow Regirock or Registeel entry. Timid is for Mew and Slaking in part, but also to beat opposing Latios if a boom hits Snorlax and the opponent is forced to try to check your Latios with theirs; it also lets you check Metagross more effectively. Speed for max base 100s, full SpA, rest in HP. Since hitting Kyogre with an Explosion is a significant strategic goal for this team, Latios is cushioned by the opponent's attempts to play around this goal.
Snorlax @ Leftovers
Ability: Immunity
EVs: 252 HP / 76 Def / 180 SpD
Sassy Nature
- Fire Blast
- Curse
- Self-Destruct
- Body Slam
Boomspam would not be complete without Snorlax. Lax is the primary Latios / generic special attacker switchin as well as another boom. It's important earlygame to get turns right with lax, as the team is pretty spikes weak, especially vs stall; thus, failing to Fire Blast a forre switchin will put you behind. The primary targets of the selfdestruct are Groudon, Kyogre, and Ho-Oh. Body Slam's paralysis can help significantly targeting these as they allow you to blow up before the target can finish you off or Substitute. Hitting Metagross or Forretress is not desirable, even if you can eliminate them thereby; conversely, hitting Latios usually frees up Registeel to itself Explode, as well as letting Groudon threaten more effectively. Blowing up early may also leave you in trouble vs Latios, but Registeel is your backup check and is usually sufficient to stave it off until you can chip or remove everything necessary. Curse makes Snorlax harder to check and therefore forces in what you want in more reliably; it can also boost Lax' Defense enough to Fire Blast Metagross. Versus Gengar, it may be necessary to stay in and Fire Blast it. EVs are just all thrown into bulk.
Regirock @ Leftovers
Ability: Clear Body
EVs: 252 HP / 96 Atk / 12 SpA / 148 SpD
Brave Nature
- Curse
- Rock Slide
- Explosion
- Fire Punch
Regirock is another Explosion, a Normal and Flying resist that also resists Fire, and more specifically a Snorlax check. Regirock unfortunately cannot do significant harm to Metagross, besides Fire Punch on the switch, and even in sun Fire Punch only 2hkos Forretress, so you need to hit it on the switch to deny Spikes. Curse boosts you versus Snorlax and powers up your Explosion, but slows Regirock down to below Forretress' speed. Again, the prime target for the explosion is Kyogre or Groudon. Regirock lives any attack from Groudon as well as Kyogre's Ice Beam, so it can Explode vs the former semi-reliably and can force the latter to Surf into Latios. Regirock may be necessary to keep around until lategame depending on the construction of the opponent's team, as it is part of the backbone against a lategame Ray or Ho-Oh. 12 SpA guarantees the 2hko on Forry, the SpD evs do something vs M2 iirc, rest in Attack.
Registeel @ Leftovers
Ability: Clear Body
EVs: 252 HP / 44 Atk / 4 SpA / 208 SpD
Sassy Nature
- Hidden Power [Fire]
- Toxic
- Explosion
- Psych Up
Another Fire attack, who would have guessed? Registeel is the backup check to Latios, Mewtwo, and Snorlax, as well as the team's third Explosion. Hidden Power Fire hits Steels, limiting Forretress to one layer, or none if hit on the switch, and letting Registeel pretend to check Metagross. Toxic hits Groudon and Kyogre less riskily than Explosion, and acquires chip on them to complete the job with Explosion later. Psych Up copies Curse boosts from Snorlax and Calm Mind boosts from Mewtwo, allowing it to Explode vs the former and break the latter's subs in two hits with HPFire in sun, either beating it or getting a chance to Explode on it as it subs to revenge with Victreebel. Explosion should hit Groudon, Kyogre, or Ho-Oh if possible. EVs boost Explosion's power a bit and are then dumped in SpD.
Victreebel @ Poison Barb
Ability: Chlorophyll
Shiny: Yes
EVs: 252 Atk / 20 Def / 16 SpA / 220 Spe
Naughty Nature
IVs: 30 Def / 30 SpA / 30 Spe
- Swords Dance
- Sleep Powder
- Sludge Bomb
- Hidden Power [Fire]
Victreebel is the core team member, and the rest of the team is designed primarily to extend the battle just long enough to remove everything that would prevent Victreebel from winning. Nevertheless, Victreebel does some important thing for the team besides just being a wincondition. Victreebel is a backup check to nearly everything; it can kill most things with enough chip and sleep anything it can't kill - once. Victreebel is often best used as a surprise, but using it midgame can be a significant benefit as well, as there is little that checks Vict that doesn't take significant damage from it, as well as risking Sludge Bomb's 30% poison chance, at the risk of revealing your gameplan. I find that against stall it's sometimes beneficial to bring in Victreebel earlier, in part because of its immunity to Toxic and therefore its ability to switch into or even hardwall certain stall staples. Of course Sleep Powder is a one-time use only, but threatening it can allow a click that can benefit you significantly. If possible, try to conserve sleep until you can target whatever mon on the opposing team is most threatening to your ability to sweep; however if you can sleep Blissey you should. Full attack, Speed beats subsalac don/ogre in sun, Def lives a CB DeoA espeed, rest in SpA for extra HPFire damage. Item isn't too important, Wide Lens would be ideal but doesn't exist in ADV, so a bit of extra Sludge Bomb damage is cool.
To win with Victreebel, Kyogre and Ray must be gone; Groudon must be heavily chipped; and Metagross, Ho-Oh, Latias, Snorlax, and Mewtwo must be chipped. Lugia walls you but can't do anything other than phase you, and if you need to you can keep coming in on it until it's out of Whirlwinds; you have lots of Swords Dance pp.
As a team that uses no fewer than three shitmons, it would not be entirely honest to say this team is good. Still, boom-based gameplans tend to be pretty effective, if you can target the booms well. In general, this team is very difficult to use, which may be why I like it so much. Your Explosions and Self-Destruct need to mostly hit the right targets, but beyond that you need to pressure whatever Steel the opponent has to keep it off the field, figure out the opponent's team enough to force in and eliminate stuff that stands in your way, and click the right buttons with Victreebel to finish the game. Of course, the real test of skill is hitting Sleep Powder; if you can't do that reliably you aren't skilful enough for this team. In any case, this team is lots of fun to use; there's nothing better than hitting a good explosion and having to wait 30 seconds for the opponent's next turn for them to reevaluate the game.
This team struggles versus certain foes to a greater extent than most teams; it would not be a stretch to call it a matchup fish. Rayquaza is a significant problem, revenging Victreebel as reliably as Kyogre but also potentially coming out much later in the game. Teams with multiple of Vict's harder checks, such as ogre+don teams, are also significant problems. Despite the fire moves on every mon, Forretress and Metagross are problems as well, with Forretress' Spikes chipping the team and breaking Vict's ability to live a DeoA Espeed, and with despite having multiple switchins for every move of Metagross the team having no mon that can switch in to every move. Forry rain is a particular pain, but rain stall is bad anyways.
This team is more fun to use than it is actually good; a more standard structure will serve you better mostly. I really like it, however.
I went through a number of versions of the team after this; I noticed trouble vs firelax and hooh, so I swapped Forretress for Regirock; I found I had trouble vs subcm stuff so I put Registeel over Metagross, which via being another Latios check let me drop Blissey for another boom in Snorlax.
The final (or at least current) version of the team is
Groudon @ Leftovers
Ability: Drought
Shiny: Yes
EVs: 252 HP / 56 Def / 120 SpD / 80 Spe
Impish Nature
- Bulk Up
- Earthquake
- Rock Slide
- Overheat
Groudon of course brings Victreebel's sun. Rather than trying to keep sun up as aggressively as possible, I usually conserve Groudon earlygame while I try to get a boom off on opposing Kyogre. Besides Drought, Groudon checks Ray and Ho-Oh, opposing Groudon, opposing Snorlax, and DeoA. A defensive spread lets it take these threats on as effectively as possible, with enough speed to reliably outspeed opposing Groudon (and possibly finish off Kyogre). Since its function on this team is primarily defensive, HPGhost isn't really necessary - it forces out what it wants to force out better with slide. Ho-Oh may stay in and fish for a burn, but even if it outspeeds and does burn getting a slide off vs hooh will usually advance your gameplan significantly.
Bulk Up is to match up better defensively vs don and lax. Slide is important to properly hit Ho-Oh in particular and Ray. Overheat is essential to prevent spikes from Forretress, as well as eliminate Metagross and Forretress before they can blow you up. I forget what the EVs do.
Latios @ Soul Dew
Ability: Levitate
Shiny: Yes
EVs: 76 HP / 252 SpA / 180 Spe
Timid Nature
IVs: 2 Atk / 30 SpA / 30 Spe
- Thunder
- Ice Beam
- Hidden Power [Fire]
- Recover
Latios checks Groudon and Kyogre. HPFire eliminates Metagross in Sun and Forretress, preventing Spikes, removing boom resists, and forcing in Snorlax to allow Regirock or Registeel entry. Timid is for Mew and Slaking in part, but also to beat opposing Latios if a boom hits Snorlax and the opponent is forced to try to check your Latios with theirs; it also lets you check Metagross more effectively. Speed for max base 100s, full SpA, rest in HP. Since hitting Kyogre with an Explosion is a significant strategic goal for this team, Latios is cushioned by the opponent's attempts to play around this goal.
Snorlax @ Leftovers
Ability: Immunity
EVs: 252 HP / 76 Def / 180 SpD
Sassy Nature
- Fire Blast
- Curse
- Self-Destruct
- Body Slam
Boomspam would not be complete without Snorlax. Lax is the primary Latios / generic special attacker switchin as well as another boom. It's important earlygame to get turns right with lax, as the team is pretty spikes weak, especially vs stall; thus, failing to Fire Blast a forre switchin will put you behind. The primary targets of the selfdestruct are Groudon, Kyogre, and Ho-Oh. Body Slam's paralysis can help significantly targeting these as they allow you to blow up before the target can finish you off or Substitute. Hitting Metagross or Forretress is not desirable, even if you can eliminate them thereby; conversely, hitting Latios usually frees up Registeel to itself Explode, as well as letting Groudon threaten more effectively. Blowing up early may also leave you in trouble vs Latios, but Registeel is your backup check and is usually sufficient to stave it off until you can chip or remove everything necessary. Curse makes Snorlax harder to check and therefore forces in what you want in more reliably; it can also boost Lax' Defense enough to Fire Blast Metagross. Versus Gengar, it may be necessary to stay in and Fire Blast it. EVs are just all thrown into bulk.
Regirock @ Leftovers
Ability: Clear Body
EVs: 252 HP / 96 Atk / 12 SpA / 148 SpD
Brave Nature
- Curse
- Rock Slide
- Explosion
- Fire Punch
Regirock is another Explosion, a Normal and Flying resist that also resists Fire, and more specifically a Snorlax check. Regirock unfortunately cannot do significant harm to Metagross, besides Fire Punch on the switch, and even in sun Fire Punch only 2hkos Forretress, so you need to hit it on the switch to deny Spikes. Curse boosts you versus Snorlax and powers up your Explosion, but slows Regirock down to below Forretress' speed. Again, the prime target for the explosion is Kyogre or Groudon. Regirock lives any attack from Groudon as well as Kyogre's Ice Beam, so it can Explode vs the former semi-reliably and can force the latter to Surf into Latios. Regirock may be necessary to keep around until lategame depending on the construction of the opponent's team, as it is part of the backbone against a lategame Ray or Ho-Oh. 12 SpA guarantees the 2hko on Forry, the SpD evs do something vs M2 iirc, rest in Attack.
Registeel @ Leftovers
Ability: Clear Body
EVs: 252 HP / 44 Atk / 4 SpA / 208 SpD
Sassy Nature
- Hidden Power [Fire]
- Toxic
- Explosion
- Psych Up
Another Fire attack, who would have guessed? Registeel is the backup check to Latios, Mewtwo, and Snorlax, as well as the team's third Explosion. Hidden Power Fire hits Steels, limiting Forretress to one layer, or none if hit on the switch, and letting Registeel pretend to check Metagross. Toxic hits Groudon and Kyogre less riskily than Explosion, and acquires chip on them to complete the job with Explosion later. Psych Up copies Curse boosts from Snorlax and Calm Mind boosts from Mewtwo, allowing it to Explode vs the former and break the latter's subs in two hits with HPFire in sun, either beating it or getting a chance to Explode on it as it subs to revenge with Victreebel. Explosion should hit Groudon, Kyogre, or Ho-Oh if possible. EVs boost Explosion's power a bit and are then dumped in SpD.
Victreebel @ Poison Barb
Ability: Chlorophyll
Shiny: Yes
EVs: 252 Atk / 20 Def / 16 SpA / 220 Spe
Naughty Nature
IVs: 30 Def / 30 SpA / 30 Spe
- Swords Dance
- Sleep Powder
- Sludge Bomb
- Hidden Power [Fire]
Victreebel is the core team member, and the rest of the team is designed primarily to extend the battle just long enough to remove everything that would prevent Victreebel from winning. Nevertheless, Victreebel does some important thing for the team besides just being a wincondition. Victreebel is a backup check to nearly everything; it can kill most things with enough chip and sleep anything it can't kill - once. Victreebel is often best used as a surprise, but using it midgame can be a significant benefit as well, as there is little that checks Vict that doesn't take significant damage from it, as well as risking Sludge Bomb's 30% poison chance, at the risk of revealing your gameplan. I find that against stall it's sometimes beneficial to bring in Victreebel earlier, in part because of its immunity to Toxic and therefore its ability to switch into or even hardwall certain stall staples. Of course Sleep Powder is a one-time use only, but threatening it can allow a click that can benefit you significantly. If possible, try to conserve sleep until you can target whatever mon on the opposing team is most threatening to your ability to sweep; however if you can sleep Blissey you should. Full attack, Speed beats subsalac don/ogre in sun, Def lives a CB DeoA espeed, rest in SpA for extra HPFire damage. Item isn't too important, Wide Lens would be ideal but doesn't exist in ADV, so a bit of extra Sludge Bomb damage is cool.
To win with Victreebel, Kyogre and Ray must be gone; Groudon must be heavily chipped; and Metagross, Ho-Oh, Latias, Snorlax, and Mewtwo must be chipped. Lugia walls you but can't do anything other than phase you, and if you need to you can keep coming in on it until it's out of Whirlwinds; you have lots of Swords Dance pp.
As a team that uses no fewer than three shitmons, it would not be entirely honest to say this team is good. Still, boom-based gameplans tend to be pretty effective, if you can target the booms well. In general, this team is very difficult to use, which may be why I like it so much. Your Explosions and Self-Destruct need to mostly hit the right targets, but beyond that you need to pressure whatever Steel the opponent has to keep it off the field, figure out the opponent's team enough to force in and eliminate stuff that stands in your way, and click the right buttons with Victreebel to finish the game. Of course, the real test of skill is hitting Sleep Powder; if you can't do that reliably you aren't skilful enough for this team. In any case, this team is lots of fun to use; there's nothing better than hitting a good explosion and having to wait 30 seconds for the opponent's next turn for them to reevaluate the game.
This team struggles versus certain foes to a greater extent than most teams; it would not be a stretch to call it a matchup fish. Rayquaza is a significant problem, revenging Victreebel as reliably as Kyogre but also potentially coming out much later in the game. Teams with multiple of Vict's harder checks, such as ogre+don teams, are also significant problems. Despite the fire moves on every mon, Forretress and Metagross are problems as well, with Forretress' Spikes chipping the team and breaking Vict's ability to live a DeoA Espeed, and with despite having multiple switchins for every move of Metagross the team having no mon that can switch in to every move. Forry rain is a particular pain, but rain stall is bad anyways.
This team is more fun to use than it is actually good; a more standard structure will serve you better mostly. I really like it, however.