I feel that the last member of this team should be something that covers up as many weaknesses as possible while still posing a significant threat to the opposing team. Let's take a look at what we have so far:
-Choice Scarf Terrakion
-Substitute Nasty Plot Darkrai
-All Out Attacker Latios
-Support Dialga
-Hazards Deoxys-S
So far, we have a solid team that can threaten a variety of Pokemon. We match up fairly well with all hazard setters, have a good offensive check to ExtremeKiller, and now we have an answer for Calm Mind Arceus (specifically Ghostceus). I have identified a few areas of weakness though:
1. No spinblocker. There isn't much we can do if something like Support Exca comes in on Latios after it has used Draco Meteor. Tentacruel can also find opportunities to spin. I feel that a spinblocker should be added unless we find something that makes our team so much stronger that we cannot possibly pass it up.
Potential pokemon we can add to fix this issue: Giratina-O, Arceus-Ghost, Giratina-A, and perhaps Sableye. The latter can find itself Tentacruel set-up bait though; Substitute Darkrai hates Toxic Spikes. Giratina-O can maul Tentacruel and support Excadrill with Earthquake and Ghostceus can set up on Tentacruel lacking Toxic while beating Excadrill with a fighting move.
2. Rain sweepers, especially Kingdra. Kabutops with Aqua Jet will be a nightmare mid-to-late game, as it can defeat Jolly Terrakion and 2HKO our entire team, and Kingdra outruns and OHKO's Darkrai, Latios, and even Scarf Terrakion! Kingdra is a pressing issue for all Weatherless teams and this one is no exception. Rayquaza does a fantastic job of revenging these threats, though it sadly cannot directly switch into them. Thunder Wave Chansey, though not recommended for a Hyper-Offense, can cripple all Swift Swimmers effectively and is light enough to avoid Kabutops' Low Kick from doing maximum damage.
Potential Pokemon we can add to fix this issue: Rayquaza, Chansey, and to a much lesser extent Ghostceus (after SR and Spikes, 252 Special Attack Ghostceus can kill most weather sweepers). Both Giratina forms check Kabutops but don't like switching into Omastar's Ice Beam and despise Kingdra's Dragon STAB.
3. Potentially susceptible to Bulky EKiller
If Deoxys-S gets only one layer of hazards down, Bulkier versions of EK could pose problems:
252 Atk Terrakion Close Combat vs. 240 HP / 0 Def Arceus-Normal: 336-396 (76.19 - 89.79%) -- guaranteed 2HKO
So a combination of Earthquake and Extremespeed will bring Terrakion to its knees, allowing EKiller to Extremespeed something else for decent damage before dying. And if Arceus is already at +2 when Terrakion comes in, it can spam Extremespeed (which 2HKO's) and hope for a critical hit, at which point our team is doomed. I would feel more comfortable with this team with extra EKiler insurance.
Potential Pokemon we can add to fix the issue: Giratina-A, Giratina-O, Sableye, Ghostceus. Sableye checks EK very well but is a weaker Pokemon in general than the Big Three. Giratina-A is the best check from a defensive standpoint, whereas Giratina-O's Dragon Tail will take a nice chunk out of it, specially considering hazards. Both physical and special Ghostceus can take on EK adequately, with Focus Blast 2HKOing and Brick Break 3HKOing.
I feel that Physical Ghostceus is our best bet, since we have more Special Attackers than Physical attackers at the moment. With that said, I am very eager to hear arguments in favor of the likes of Rayquaza, Giratina-O, etc.
