First let me say I feel for you. Deaths that seem arbitrary really hurt.

2* wolves only appear in the vanilla game at night.

So either you are modding to tame 2* wolves easier, in which case this isn't the game's fault, or you went into the mountain at night, or so early in the morning that the night creatures had no chance to despawn.

Therefore this is 100% avoidable, by staying out of a new biome at night, and only fighting there in the day until you have the food and gear from that biome.

Mistlands will give you nightmares, there you CAN have 1*/2* seekers jump you out of the mist and wreck you. Properly geared they will not 1-shot you, but depending on your reaction time, you may never get to act, as they can 2-shot you, even with top tier plains gear and food. They can also knock you into pits, water, or off high ledges, all of which are pretty much guaranteed death when you are in plains gear.