General

Mercedes could level to 200 without killing monsters

As we all know, Mercedes have a beginner skill called elf's blessing:

Elf's Blessing: With the blessing of the ancient elves, you can return to Eurel and also permanently gain 10% experience.
Return to Eurel (cooldown is 1800 seconds), gain 10% extra experience.
the cooldown is for 30mins, meaning you can get 20%/hr for doing nothing. This is particularly slow for low levels, but quite attractive for higher levels.
This means it would be possible, if you used the skill every 30 mins, 24/7, to level to 200 in ~41.46 days.
Not counting the fact you can speed up the process by leveling yourself until it starts slowing down too much.