I don't really see many people use it and it is a good Pokemon with decent coverage.
Although Typhlosion has access to Eruption, passable coverage, and a solid Speed tier, it falls short as a wallbreaker due to it failing to reliably break bulky Water-types like Vaporeon and Slowking as well as other Fire-resistant Pokemon such as Hariyama and Druddigon. Additionally, Typhlosion faces immense competition as a Fire-type from Magmortar and Delphox. Magmortar is a better wallbreaker due to its greater Special Attack and coverage options, while Delphox is much more versatile, being able to employ multiple sets effectively.
Tl;dr it can't break through bulky Pokemon like Slowking and it's generally outclassed by Magmortar/Delphox.
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