Nominating Chansey from UR to C.
Let's just be honest - this mon is just seen as a worse Blissey a lot of the time. And yeah, Blissey fits on a wider range of teams than its little sister. But despite that, I feel Chansey has clearly proven its niche in the tier, especially on Double Defog teams - from stall to balance to BO, though especially the former. Double Defog is not difficult to fit right now - just look at the amount of Lando/Torn teams or even Lando/Corv or Lando/Fini, etc etc. In many cases teams will already have double defog and in that case will pretty much always prefer Chansey to Blissey. This way, Chansey becomes a Blissey that has significantly better bulk meaning it can come in on mons like Dragapult's U-Turn's much more often than a Blissey can given good hazard control.
0- Atk Dragapult U-turn vs. 248 HP / 252+ Def Eviolite Chansey: 70-83 (9.9 - 11.8%)
0- Atk Dragapult U-turn vs. 252 HP / 252+ Def Blissey: 96-114 (13.4 - 15.9%)
The difference between 10% and 14% is significant long-term.
It also completely negates the risk of a 2HKO from modest scarf or twistedspoon Tapu Lele:
252+ SpA Twisted Spoon Tapu Lele Psyshock vs. 248 HP / 252+ Def Eviolite Chansey in Psychic Terrain: 297-351 (42.2 - 49.9%) -- guaranteed 3HKO
252+ SpA Twisted Spoon Tapu Lele Psyshock vs. 252 HP / 252+ Def Blissey in Psychic Terrain: 408-480 (57.1 - 67.2%) -- guaranteed 2HKO
As well as CC on specs Aegi:
0- Atk Aegislash-Blade Close Combat vs. 248 HP / 252+ Def Eviolite Chansey: 274-324 (38.9 - 46%) -- guaranteed 3HKO
0- Atk Aegislash-Blade Close Combat vs. 252 HP / 252+ Def Blissey: 376-444 (52.6 - 62.1%) -- guaranteed 2HKO
And, as a nice bonus, doesn't give a useful item to Trick Blacephalon.
It even matches up better against trapper Tran due to its better special bulk:
0 SpA Heatran Magma Storm vs. 248 HP / 8 SpD Eviolite Chansey: 85-102 (12 - 14.5%) -- guaranteed 5HKO after trapping damage
0 SpA Heatran Magma Storm vs. 252 HP / 4 SpD Blissey: 103-123 (14.4 - 17.2%) -- 64.9% chance to 4HKO after trapping damage
^It can Seismic Toss an extra time in this example (though in practice this really depends on prior chip, tran EVs, misses, taunts/toxics etc.)
It also completely walls bulky Fiery Dance Volc (if people run that?):
+6 16 SpA Volcarona Fiery Dance vs. 248 HP / 8 SpD Eviolite Chansey: 288-339 (40.9 - 48.2%) -- guaranteed 3HKO
Anyways, calcs aside, the usage data on Chansey is extremely telling. Its viablity ceiling is 95, making it tied for the highest at 1825 elo in February's usage stats. Of course that doesn't make it an S rank automatically but it's like top 50 for sure, right? Its usage last month surpassed current-OU mons in Regieleki, Victini and Scizor as well as high-ranked threats such as Arctozolt, Hawlucha, Nihilego and Slowking (Johto). Since the VRs are in part a resource for new players unfamiliar with the tier I feel it's crazy to have such an impactful mon be completely absent from the rankings. Personally I don't even like using this mon or its boots-wearing counterpart but they are important mons to the tier and so should be ranked. I've suggested C tier but C+/B-, or at least C- as a minimum would be reasonable, too. I guess the fact that Xatu is still ranked for a stall niche yet Chansey is not must be because of the spacing out of VR updates, because the data clearly shows the latter is significantly more impactful on the OU metagame than the funny green bird right now. Anyways. That's my ramble over. TL;DR pink blob good sometimes. Thanks for reading.
Let's just be honest - this mon is just seen as a worse Blissey a lot of the time. And yeah, Blissey fits on a wider range of teams than its little sister. But despite that, I feel Chansey has clearly proven its niche in the tier, especially on Double Defog teams - from stall to balance to BO, though especially the former. Double Defog is not difficult to fit right now - just look at the amount of Lando/Torn teams or even Lando/Corv or Lando/Fini, etc etc. In many cases teams will already have double defog and in that case will pretty much always prefer Chansey to Blissey. This way, Chansey becomes a Blissey that has significantly better bulk meaning it can come in on mons like Dragapult's U-Turn's much more often than a Blissey can given good hazard control.
0- Atk Dragapult U-turn vs. 248 HP / 252+ Def Eviolite Chansey: 70-83 (9.9 - 11.8%)
0- Atk Dragapult U-turn vs. 252 HP / 252+ Def Blissey: 96-114 (13.4 - 15.9%)
The difference between 10% and 14% is significant long-term.
It also completely negates the risk of a 2HKO from modest scarf or twistedspoon Tapu Lele:
252+ SpA Twisted Spoon Tapu Lele Psyshock vs. 248 HP / 252+ Def Eviolite Chansey in Psychic Terrain: 297-351 (42.2 - 49.9%) -- guaranteed 3HKO
252+ SpA Twisted Spoon Tapu Lele Psyshock vs. 252 HP / 252+ Def Blissey in Psychic Terrain: 408-480 (57.1 - 67.2%) -- guaranteed 2HKO
As well as CC on specs Aegi:
0- Atk Aegislash-Blade Close Combat vs. 248 HP / 252+ Def Eviolite Chansey: 274-324 (38.9 - 46%) -- guaranteed 3HKO
0- Atk Aegislash-Blade Close Combat vs. 252 HP / 252+ Def Blissey: 376-444 (52.6 - 62.1%) -- guaranteed 2HKO
And, as a nice bonus, doesn't give a useful item to Trick Blacephalon.
It even matches up better against trapper Tran due to its better special bulk:
0 SpA Heatran Magma Storm vs. 248 HP / 8 SpD Eviolite Chansey: 85-102 (12 - 14.5%) -- guaranteed 5HKO after trapping damage
0 SpA Heatran Magma Storm vs. 252 HP / 4 SpD Blissey: 103-123 (14.4 - 17.2%) -- 64.9% chance to 4HKO after trapping damage
^It can Seismic Toss an extra time in this example (though in practice this really depends on prior chip, tran EVs, misses, taunts/toxics etc.)
It also completely walls bulky Fiery Dance Volc (if people run that?):
+6 16 SpA Volcarona Fiery Dance vs. 248 HP / 8 SpD Eviolite Chansey: 288-339 (40.9 - 48.2%) -- guaranteed 3HKO
Anyways, calcs aside, the usage data on Chansey is extremely telling. Its viablity ceiling is 95, making it tied for the highest at 1825 elo in February's usage stats. Of course that doesn't make it an S rank automatically but it's like top 50 for sure, right? Its usage last month surpassed current-OU mons in Regieleki, Victini and Scizor as well as high-ranked threats such as Arctozolt, Hawlucha, Nihilego and Slowking (Johto). Since the VRs are in part a resource for new players unfamiliar with the tier I feel it's crazy to have such an impactful mon be completely absent from the rankings. Personally I don't even like using this mon or its boots-wearing counterpart but they are important mons to the tier and so should be ranked. I've suggested C tier but C+/B-, or at least C- as a minimum would be reasonable, too. I guess the fact that Xatu is still ranked for a stall niche yet Chansey is not must be because of the spacing out of VR updates, because the data clearly shows the latter is significantly more impactful on the OU metagame than the funny green bird right now. Anyways. That's my ramble over. TL;DR pink blob good sometimes. Thanks for reading.