Arceus-Grass has a clear niche in Ubers as a hard counter to Arceus-Ground and Arceus-Rock and as a solid check to Arceus-Water and defensive variants of Primal Kyogre. Arceus-Grass's unique mono-Grass typing gives it a key resistance to Ground and a neutrality to Rock, which allows it to also deal with threatening sweepers such as Primal Groudon that lack a Fire-type move. Despite its common weaknesses to Flying-, Ice-, and Fire-type moves, Arceus-Grass can be difficult for offensive teams to switch into due to its potent coverage that can easily overcome would-be checks, such as Rayquaza, Mega Salamence, and Mega Lucario. Several balance cores, such as Primal Kyogre + Celesteela and Primal Kyogre + Arceus-Ground, also struggle to deal with Arceus-Grass, which can make it surprisingly dangerous in some matchups. Unlike most offensively inclined Arceus formes, Arceus-Grass can afford to invest in bulk due to Grass Knot having a Base Power of 144 against most Ubers. Unfortunately, Arceus-Grass's many weaknesses make it difficult to bring into play, as many Pokemon carry moves that can hit it super effectively. This diminishes its effectiveness in practice. Arceus-Grass also struggles with four-moveslot syndrome, as it is forced to run Grass Knot, Ice Beam to lure and KO Mega Salamence, and Recover to ensure it remains useful throughout a match. This means it cannot run both Stone Edge and Fire Blast and is forced to settle for the latter move due to it hitting a wider breadth of Pokemon, rendering it extremely weak to Ho-Oh. While Arceus-Grass has a decent matchup against offensive teams, Arceus-Grass has a terrible matchup against stall teams, where checks such as Toxapex, Ho-Oh, and Lugia are ubiquitous and render Arceus-Grass dead weight. This is complicated by how common defensive teams are in the Ubers metagame. Arceus-Grass is very vulnerable to status, especially poison and paralysis, and has a very poor matchup against Mega Gengar. Arceus-Grass's positive qualities allow it to function very well in certain matchups, but it requires considerable team support to overcome its offensive and defensive shortcomings. This can make it difficult to justify on most teams.