There is a traveling merchant that appears in Alfataria and the Fields of Fum alternately between years who will eventually sell Chilly Gel, but you can also find it in cold and damp places like Veo Lu Sluice or Conall Curach. Ice element enemies may carry Chilly Gel as well. Your prime targets will be the Ice Bombs, Snow Mus, Water Flans and other enemies with the Ice element.

You can find them anywhere, as it has nothing to do with the climate. Electric element enemies may carry Thunderballs as well, so your prime targets will be the Thunder Bombs, Electric Jellyfish and other enemies with the Electric element. Thunderballs can be bought from your local merchant if he has developed good relationships with his son/daughter in your caravan.

DO SOMETHING!!!