Cold Mastery

[kevN]

If orb and nova is ur main attack, how many points should u put in COLD mastery since it doesnt increase damage, but increases chance of penetration.

[Epsilon Eyez]

It doesn't increase chance of penetration, it effectively removes cold resistances (but not immunities), resulting in easier killing of creatures. I recommend 1-10 points depending on tastes and needs.

Definitely put one point right away though. Helps a bunch.

[Harleyquin]

Most builds aim for 17 after skills or maxed out with skills to bring it over 20. Reason being the maximum a monster can go is -100 to cold resistance (lvl17) or to bring a cold resistant monster (E.g. Mephisto) as close to -100 as possible

[EnerSense]

If orb and nova is ur main attack, how many points should u put in COLD mastery since it doesnt increase damage, but increases chance of penetration.

If you have the points to spare, put it in cold mastery. Level 17 is enough for monsters without cold resistances. I found that 1 point is enough as long as you have items that give + to cold skills or all skills. I personally don't think putting points enough for level 17 cold mastery is necessary IMHO.