This game requires a lot of planning because you can’t change class and relay on a lot of money for equips, pets, attributes, scrolls…
You have to understand your first char will always suffer the most so usually pick the easiest or the one you will benefit the most like archer with free pet or swordsman fast paced face-roll class.
Keep in mind pets are account wide. Any new char can use it.
If you pick cleric first you will obviously be able to do everything too, even solo, but will be really really slow.
Heal, little damage, heal, heal, little damage…
Until you can actually back it up with money.
Everything changes when you have Arde Dagger
Or max attributes
Or best in slot gear
Or infinite pots
Etc.
I’ve seen Clerics lv40 with Sac + 150 blessing damage /every hit
Also lv75 with Sac + 150 Bless + 150 Arde dagger /every hit
Monk Double punch + Sac + Bless + Arde dagger /every hit
…
That’s without having to buy scroll, because any other class could do same thing spending loads money buying scroll with 1h Bless + Sac
Hope you understand what I mean

