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Garchomp/lando with toxic is a good check to volc, and in general just a really good move for them. Obviously it’s not a hard counter like heatran but it does put volc on a timer
Even if it resists leaf blade and flamethrower it has basically no defensive benefit, plus with heatran on your team kartana and blacephalon will be clicking knock off and shadow ball, respectively the vast majority of the time. Scarf dragapult isn’t really viable because it has pretty bad...
This is a niche pick but you could try blizzard over ice beam on kyurem. Been thinking about this set recently and blizzards destructive power would be insane
I feel like making lele timid would help against kyurem, you’d lose a bit of breaking power but being able to possibly outspeed kyurem would ease the matchup a bit
Maybe give him advice on how to improve his team (example: what dragons to add) instead of pointlessly criticizing his team without helping. New players may not know that it’s optimal to have multiple dragons on a drag mag team.