Ferrothorn provides a fantastic role as a Spikes setter that can keep them up reliably against most Defoggers in the tier. Knock Off removes the Leftovers or Heavy-Duty Boots from many of its switch-ins, such as Zapdos, Corviknight, Tangrowth, and Heatran, making entry hazards more effective against them. As its only form of recovery besides Leftovers, Leech Seed improves its longevity and lets it slowly whittle down Pokemon like Garchomp and Ash-Greninja. Power Whip improves its mostly passive presence and pressures Water-types like Ash-Greninja, Tapu Fini, Mega Swampert, Gastrodon, and Slowking. Body Press can be run to pressure Kyurem, Heatran, and Kartana from switching in and beat Magnezone in rain. Thunder Wave can provide utility in crippling fast wallbreakers like Ash-Greninja and walls like Corviknight for its teammates. Iron Barbs is Ferrothorn's best ability, chipping pivots like U-turn Rillaboom and Landorus-T. A specially defensive EV spread allows it to handle Pokemon like Clefable, Tapu Lele, and Greninja more easily. 232 Special Defense EVs ensure it survives three Choice Specs Greninja's Dark Pulses from full HP.

Ferrothorn fits best on balance and bulky offensive teams in need of a wall. Ferrothorn synergizes well with other entry hazard setters such as Stealth Rock Landorus-T and Garchomp to stack up chip damage. Landorus-T also does well at providing a Ground immunity, as Pokemon like Garchomp and opposing Landorus-T can overwhelm Ferrothorn once boosted due to its reliance on passive recovery. Garchomp can also pressure Defoggers like Corviknight and Zapdos, preventing them from safely removing its entry hazards. Garchomp, Tapu Fini, Tyranitar, and Toxapex check Fire-type threats like Heatran, Mega Charizard Y, and Volcarona. Ash-Greninja can also threaten the aforementioned Pokemon and also set Spikes alongside Ferrothorn. Ferrothorn appreciates Dark-resistant Pokemon like Clefable and Tapu Fini to handle Ash-Greninja more easily. Spikes is a boon for teammates like Reuniclus, Clefable, and Garchomp, as they appreciate it wearing down their checks and punishing switches harder.