[Arceus@Leftovers Impish, Will-O-Wisp / Return / Recover / (Roar/Perish Song) + Chansey@Eviolite Calm, Toxic / Wish / Softboiled / (Seismic Toss/Stealth Rock)]
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[Arceus Combination / Defensive Combination]
[Ah, these two wonderful walls. One of them creates a very sturdy physical wall, and the other is probably the best special wall in the Ubers metagame. The former one being, Wallceus of course and the latter is Chansey. Wallceus can take care of physical threats and shut them down with Will-O-Wisp, something Chansey obviously can't do with her base 5 Defense, or phaze them out with Roar in case they try to set up or use Perish Song in order to limit their sweep. While Wallceus takes care of physical threats, Chansey does the job on the special side, with her enourmous special bulk of 642 HP and 508 SpD. Chansey can also take care of special threats with Toxic; that will make them die very quick as Toxic damage gets bigger each turn.]
[Entry Hazards, especially Toxic Spikes, will shut this combo down rather quick. Wallceus does not enjoy being poisoned at all, and Chansey does not appreciate it either. Spikes will cause 25% damage each switch in assuming 3 layers are laid, and since this combo alternates between physical bulk and special bulk, you're going to switch a lot, causing more damage to Wallceus or Chansey. Plus, this combo does not appreciate hard hitting moves like SpecsOgre's Water Spout, as Chansey won't be able to take them forever.]
[A simple way to fix this is to use another combination; Ferrothorn and Tentacruel. This combination is rather common in Ubers, combined with Kyogre to boost its effectiveness by abling allowing Tentacruel's ability, Rain Dish, to work and by lowering Ferrothorn's x4 Fire- weakness to x2. Tentacruel can spin away hazards, which is mentioned above, can cripple this combination. While Tentacruel Rapid Spins hazards away, it can also set hazards among with Ferrothorn, and since Wallceus and Chansey wall a big variety of Pokemon, they will switch out and take damage each turn.]