After a great showing by Tom bus on his youtube I think archeops and cacturne both deserve
D rank. Archeops is an effective suicide lead which hits hard with shell smash and if defeatist is activated it can fire off endeavours. The combination of taunt and stealth rocks also allows archeops to prevent defog and keeping the rocks up, it can also head smash to kill itself when in low health to prevent defog and rapid spin. Cacturne is slightly more niche and less reliable than archeops but as a focus sash lead the combination of sucker punch, swords dance and spikes allows to stack spikes whilst being an effective offensive presence for offensive teams. It can also run counter to punish leading lando-t which will u-turn on most occasions aswell as most physical attackers as they will likely bring cacturne close to its sash. Both of these mons struggle against sableye although cacturne can SD + Seed bomb against calm mind variants but straight up loses to foul play sableye. All in all for their effectiveness in damaging the opposition with lures such as endeavour and counter and their high attack stats these mons deserve
D for their roles as suicide leads. Evidence:
Archeps is not near as bad as Slaking, but no, NO, NOOO... Archeops' horrible ability and weak deenses causes that a heavy hitting metagame Archeops has forced to do a Focus Sash set and when a 1HP it can't attack well because of his horrible ability.
If you want to do something similar, do this (is almost unviable but it's clearly better thsan Archeops).
Aerdactyle @ Aerodactylite/Focus Sash
Ability: Presure
EVs: /252 Atk/24 Def232 Spe
Jolly/Adamant Nature
-Stealth Rock
-Stone Edge/Rock Slide/Aerial Ace
-Taunt/Aqua Tail/Earthquake
-Roost/Taunt
Or use many of the Stealth Rock setters available like Aelf, Infernape, Mamoswine, Terrakion, Garchomp, among others.
About Cacturne, spike stacking is not good this gen but if you want to use Spikes, use bulky setters like Ferrothorn or Skarmory.
If you want suicide Spikers:
Froslass @ Focus Sash
Ability: Cursed Body
EVs: 4 HP / 252 SpA / 252 Spe
Timid Nature
- Taunt
- Spikes
- Destiny Bond
- Ice Beam
But in no way, Archeops and Cacturne are near viable in OU. In all other words, I will nominate them for both pokemon being "Blacklisted".
Also, I want to nominate Meta Metagross for "Conclusion Reached" Pokemon, because it's clear that it's the best Pokemon of the OU metagame and there isn't any reason to go out of S.
I nominate Mega Lopunny down to A+. I still think that Lopunny is one of the best Pokemon of the metagame and is even better than the average A+ Pokemon, but because it competes with Mega metagross (who is vastly superior).
I'm also thinking of if we should add an E ranking and add Venomoth here. it appears that the OU metagame is too hostile for Venomoth to be viable. It has to be E ranking because it's BL.