You can get resistence against X from potions and you find a lot of those in the game and they last until you rest.
Based on this
post, there appears to be 8 in the game. In my current Patch 4 "100%" save I have 6. I likely missed a couple, or there may be a degree to RNG when it comes to loot. Regardless, it's a decent amount if you're only using it for 1 character, but 8 potions will only last the party for 2 rests.
Note, you also cannot stack the resistance potions (but it does work with the spell). So in the EA right now, you can cast the level 2 Protection from Poison spell and drink any other Elemental potion to have 2 resistances.
I may be wrong but I'm pretty sure vendor potions restock after every long rest. I haven't counted who has what at any stage but that basically allows a steady supply if the vendor has the common potions.
Right. I just took a look - the only vendor I can find having fire resistance potion is the Gnome lady in the Underdark (at the Myconid Colony), and she'll restock 1 potion on every long rest.
To be fair, I wouldn't be surprised if the later vendors (i.e. at Baldur's Gate) restocks 3-4 resistance potion that will essentially let the party have resistance to 1 type of elemental damage at all time.
Even in a dedicated warlock build, the famed master of solo's and uber-optimized gameplay, sin tee, doesn't even use a Tiefling. Surprise, it's yet another elf. Who knew, with the incredibly trove of advantages sunk into one race, that +2 stats to a relevant attribute would be hardly worth the trade. It's also why come lv4 most people are not even taking the extra 2 bonus attributes, but instead picking up wizard/warlock initiate or grabbing medium armor proficiency.
That's because he's using a
High Half Elf, who gets +2 CHA and 2x +1 to Any stats (including DEX and CON which a Warlock needs more than INT). Half-Elves are the S-Tier race choice for any CHA-based character, in PnP and this game.
Wouldn't change much, though. In sin tee's solo wizard (shield dwarf wizard) video he goes battlemage and with a 2H hammer since the Minotaurs are weak to bludgeoning damage, he consumes an oil of sharpness and potion of hill giant strength and proceeds to one shot the minotaur with a single swing.
As an unrelated side-note, it's not that Minotaur's are actually weak vs. bludgeoning - one of the two minotaur actually wears a magical necklace (Amulet of the Unworthy) that grants slashing resistance and bludgeoning vulnerability. The other takes normal damage. I guess it's supposed to be the "trick" to the encounter.
