Potion of Haste
Potion of Invisibility
Potion of Giant Strength
Are all too abundant and OP. You can murder anything just spending petty cash. It's much worse with Extra Attack now that the effects are also multiplied. Paladin can now add smite damage on top.
Wyvern Poison is really OP too, but at least you can't buy it.
Larian should be downplaying the lethal alpha strikes in this game, not encouraging them by spammimg cheap OP potions everywhere. And rework the way surprise attacks work so you don't get double surprise rounds before initiative kicks in.
