Find the Torchlight 2 save folder

I found it in the area "The Sundered Battlefield". There is a small instance called 'Notch's Mine', which contains a few creepers.

It is worth keeping in mind that since Torchlight 2's areas are put together randomly, it could be anywhere.

Firstly this mode WILL require you to be carefule more than the others. The damage spike from the monsters means you are vulnerable to be OHKO(One-hit KO) with certain monsters. The difficulty is visible from the beginning. So here is the excerpt from a thread I had started on the official forums HCE help/guidelines. Credits to miniminionette on runic games forums

1. Always kite the mobs around. You'll take too much damage if you stick to one place. Every class has some form of escape mechanism, ala, "oh shit" buttons; learn to use them effectively in the offense/defense.

2. Every class has some form of Crowd Control, whether through slows, stuns, immobilization or other effects. Use them efficiently!

3. Summons are your HCE char's best friend!~ Always have 2 - 3 summon spells on your pet to help mitigate some damage.

4. During Boss Fights, focus on the trash mobs first, boss later. They do more damage than the boss due to their quantity.

5. Always let your pet start every battle if you are unfamiliar with the boss mechanics. Don't leeroy the fight. Study the battlefield.

6. If you cant stack ADR (all damage reduction), stack % Reflect Gems on your gear instead; most of the damage you'll receive will be ranged attacks.

7. A shield is your best friend, always have one in handy for very tight fights.

8. Target Priority during trash mobs are:Chargers, Casters, Mobbers and anything else. Chargers first because casters in general have predictable attacks and you can avoid them, chargers can sometimes put you in corners leading to death.

9. Always be at least 3 - 5 levels ahead of the mobs; those extra levels help.

10. Town Portal whenever possible; no shame in running away to fight another day.