Cofagrigus
Overview
At first glance, Cofagrigus seems to be a promising Pokemon. It has an excellent base 145 Defense stat, meaning it can take virtually any resisted or neutral physical hit. 105 Special Defense is very good for a physical wall, but a sad 58 HP stat keeps Cofagrigus from being an overall great wall. Cofagrigus has offensive potential as well, since 95 Special Attack isn't half bad. Cofagrigus has a Mono-Ghost typing, enabling it to wall Medicham, Physical Virizion, and Escavalier easier than other walls. As far as competition, defensive Cofagrigus does not face too much. Spiritomb has a better movepool, priority, and isn't as slow. Jellicent has recovery, water immunity, higher HP, and is faster. However, Cofagrigus has an edge over both of them with its insanely high defense and Mummy. Nasty Plot Cofagrigus has competition from Hoopa and Mismagius, who are faster and stronger but less bulky. It's safe to say that the metagame is pretty even with Cofagrigus right now. On one hand, there are a plethora of Fighting-types and physically offensive Pokemon just waiting to get burned. On the other hand, there is a metagame ridden with special Dark and Ghost types such as Houndoom, who will use burns to get fuel its evil fires, and Hoopa, whose 150 Special attack will decimate you in your Egyptian grave (yes, I do realize this is overly dramatic...). Cofagrigus is also somewhat of set up fodder, so be careful. Overall, Cofagrigus has a solid niche in being a physical wall or a sweeper.
Sets
Cofagrigus has two distinct sets - Defensive and Trick Room + Nasty Plot. Both use a different set of moves and require a different playstyle. In my testing, I came to the conclusion that Defensive Cofagrigus is better right now due to its ability to stop the majority of RU's physical attackers. Trick Room Nasty Plot, which I will abbreviate to TRNP because the whole thing is a pain to type, also takes frustratingly long to set up, meaning the opponent has two turns instead of one to act against Cofagrigus. Defensive Cofagrigus will usually run Leftovers to better serve as a wall. TRNP Cofagrigus will also run Leftovers to become bulkier and have passive recovery. As far as Abilities, Cofagrigus has Mummy, which goes along with its theme of annoying physical attackers. Mummy is a helpful ability, to say the least. I'll go over the top moves for Cofagrigus, and percentages will even be thrown in this time!
|74.178%|
Will-O-Wisp - Will-O-Wisp burns most physical attackers, weakening them for sometimes the whole game. This helps mitigate threats that otherwise could prove to be a problem for the rest of your team. An amazing asset for Defensive Cofagrigus
|53.716%|
Shadow Ball - Used on both sets, Shadow Ball is used to attack opponents for damaging STAB. Pokemon like Hoopa and Medicham particularly hate this move. This also has a small chance to lower Special Defense.
|51.814%|
Pain Split - This recovery, although not reliable, is the best Cofagrigus has. It can deal damage while recovering health at the same time, which can often be crucial. Another great asset for defensive Cofagrigus.
|42.062%|
Hex - This is an alternative to Shadow Ball commonly seen on defensive sets due to it having good synergy with Will-O-Wisp and Toxic Spikes. Hex also works well with another status spreader, like Alomomola.
|31.883%|
Trick Room - The essential part of the TRNP combo. This basically allows Cofagrigus to use its low speed to its advantage and poke a hole or clean up the opposing team. Cofagrigus could also serve as a setter for dedicated Trick Room teams.
|20.667%|
Toxic Spikes - Cofagrigus is a good Toxic Spikes setter and one of the only relevant ones, making Cofagrigus a help on Hazard Stack since it doubles as a spinblocker. Be careful with this, since it clashes with Will-O-Wisp, arguably Cofagrigus's most important tool.
|18.425%|
Nasty Plot - The second part of the TRNP set which allow Cofagrigus to set up and deal big damage to the opposing team. Not really much else to say about this.
|16.512%|
Hidden Power Fighting - This move rounds out TRNP. It allows Cofagrigus to hit Normal-types and also hit most Dark types for super-effective damage.
|14.729%|
Haze - A neat option for defensive Cofagrigus that allows it to stop certain setup sweepers in a pinch. If Cofagrigus can take a hit from the said sweeper, than Haze will eliminate the stat changes. This certainly isn't amazing, but helpful under the righ circumstance.
|12.399%|
Calm Mind - Unfortunately, Cofagrigus is not a very good Calm Mind user as it is susceptible to being worn down and does not have a good move to Mono-Attack with, since Normal-types are immune to Shadow Ball. This may have some potential, but not much.
|12.238%|
Rest - A reliable recovery move that can be used in combination with Chesto Berry and/or Sleep Talk, but Cofagrigus prefers Leftovers more and being put to sleep is very unfavorable, since Cofagrigus is already set-up fodder. An interesting, but not very good option.
|11.295%|
Knock Off - Knocking off an item is always great utility, but Cofagrigus's Attack stat is so mediocre it isn't even worth it, at least in my opinion. This could be an option for teams without a Knock Off user already.
Team Options
Cofagrigus could be paired with a special wall such as Registeel or Togetic to complement its defensiveness. Entry hazards such as Spikes or Stealth Rocks pair nicely with the switches Cofagrigus forces on physical attackers. A Dark-type provides the most type synergy with Cofagrigus, since one can take Dark-type and Ghost-type attacks and Cofagrigus can take Fighting-type and Bug-type attacks in return. In this regard, Sneasel, Drapion, Absol, and Houndoom all make for good partners. Virizion, Mawile, and Mega-Audno can all take Knock Offs. TRNP Cofagrigus appreciates slow wallbreakers such as Rhyperior or Mega-Camerupt to pave the way for a sweep and also have good synergy with Trick Room.
Hope I helped some people! God, this took a long time to write.