Magmar is one of the best offensive Pokemon in GSC NU. It can be difficult to wall without Ninetales due to its excellent coverage, letting it hit a lot of the tier quite hard. Magmar also brings decent defensive utility to its team thanks to its usable Special Defense, which means Magmar is notably only 4HKOed by Xatu's Psychic. Magmar is also quite fast for the tier, outpacing threats like Kingler and Hitmonlee. However, Magmar does face competition from other Fire-types that bring more to a team; Ninetales brings huge defensive potential, and Rapidash is an incredibly fast lead with Hypnosis. Magmar's STAB Fire Blast threatens to 2HKO a large portion of the tier, notably Xatu, and can be powered up even more with Charcoal. Thunder Punch damages Water-types such as Octillery and Kingler quite a lot and gives Magmar coverage for Flying-types that won't miss unlike Fire Blast. Hidden Power Grass can be used instead, as it OHKOes Graveler, can 2HKO Sudoowodo with Spikes up and additional minor chip damage, and can reduce prediction between deciding to use Thunder Punch to hit Octillery or Fire Blast to hit Dugtrio while barely being weaker than Thunder Punch against Octillery; however, it comes at the cost of significantly reducing Magmar's DVs and losing out on Thunder Punch's ability to hit Flying-types with perfect accuracy. Cross Chop heavily threatens Dewgong, damages Wigglytuff and Dunsparce harder than Fire Blast, and has a chance to land a critical hit through the Normal-types' Curse boosts. Lastly, Sunny Day powers up Magmar's Fire Blast to a staggering degree, notably 2HKOing even the incredibly bulky Dewgong while lowering the power of Water moves and reducing the accuracy of Thunders aimed at Magmar, even allowing Magmar to become a solid answer to Dewgong if it can gain entry on a usage of Ice Beam or Rest. Hidden Power Ground can be used instead to hit opposing Fire-types hard while also 2HKOing Chinchou after Spikes damage, though it still cannot 3HKO the faster and RestTalk-using Ninetales without Spikes. Thief can also be chosen in order to weaken bulky Pokemon like Octillery, Ninetales, and Xatu, making it easier for Magmar itself to wallbreak later in the game while also supporting teammates, though it makes it significantly harder to switch Magmar into battle with Spikes up due to lack of Leftovers before using Thief.

Magmar pairs well with Water-types, most notably Chinchou, which beats the Water- and Fire-types that can beat Magmar one-on-one; in return, Magmar beats the Grass-types that wall Chinchou. Pokemon with Explosion or Self-Destruct such as Weezing and Sudowoodo can try to take out bulky Water- and Fire-types that give Magmar trouble. Magmar also pairs well with other fast offensive Pokemon such as Fearow, Xatu, and Primeape to overwhelm the opponent's defensive core with Spikes down, as they can force the defensive Pokemon to switch around and take chip damage, which can leave the opponent's team weakened enough to be cleaned up. Finally, Magmar makes for a very good recipient of Baton Pass, especially Growth passes from Flareon.