[QUOTE="Finchinator, post: 8326486, member
Clefable, Ferrothorn, Conkeldurr, Rotom-Mow, and Reuniclus all do the trick
[/QUOTE]
I can add one to the list, eldegross, monograss isn't the best typing but unlike ferrothorn isn't 0HKO by any fire type, and can actually withstand fire blast from dragapult, and if it land Leech seed on that turn, can Heal back up with Protect and Leftovers and take another one, it also has synthesis for reliable recovery and rápid spin. It is also very easy to keep healthy due to it having a great ability in Regenerator. I know it's not OU, the team I'm using it on is working well and if I reach a good placement with it I'll nominate it with further knowledge. But regarding seismitoad, you can l safely Leech seed and either sap him or whoever he Switches into, as no one wants to risk eldegross having a grass type attack.
P. S. : almost 2020 here on Spain, Happy New Year in advance everybody!!