Poliwrath

A habitat matching this ambience raises Comfy Level faster. Time and weather gate whether a Pokémon turns up at a habitat at all — though light overrides the clock: a night Pokémon spawns at any hour if its habitat sits somewhere dark such as a cave or underground, and a day Pokémon spawns at night if its habitat is ringed with light.

Give or place anything matching these and both friendship and Comfy Level rise much faster — a matching item lays down with a bigger sparkle. For a Pokémon with the Trade specialty, matching items are also worth 50% more on the scale.

1 Lots of water

30+ items

Resort hammockTable settingPaper Party cupsSoda floatShaved iceModern sinkToiletSinkBathtime setCleaning suppliesShowerBathtubBouncy blue bathtubHumidifierFunky diffuserWater basinCanoeInflatable boatBeach parasolHorsea fountainFire hydrantSprinklerMystic WaterWater pillar quarterHoppip water bottleJuice trioTeaware setBottled shipGyarados fountainBubble machine

2 Cleanliness

14+ items

Waterproof seatLarge mirrorModern sinkWashing machineToiletSinkTowel rackBathtime setCleaning suppliesShowerBathtubBouncy blue bathtubWater basinCooler

3 Construction

7+ items

SandbagsMetal drumConstruction suppliesIron pipesWheelbarrowIron-scaffold plankIron scaffold

4 Exercise

5+ items

Punching gameWobbuffet WobblerPunching bagBikeBeach volleyball set

5 Group activities

Flavour: spicy

9 foods

Fresh carrotCrouton saladElectrifying soupHealthy soupCarrot breadBread bowlChili sauceExplosive hamburger steakRed-hot smoothie

Two caveats. The game lists these five in a fixed order, but no source says the first counts for more than the fifth — the numbers are the in-game order, not a strength ranking. And the item lists are incomplete: Serebii marks them as still being filled in, so each count is a floor, not a total.