I restarted the game to do the non calamity path and because my save was so ancient and collected some interesting and weird bugs due to being imported into newer versions.
I discovered that if you know what you are doing grinding is so vastly lower and the game goes pretty fast.
first skill you want to buy is hellfire That spell is fantastic and just knowing to buy it first makes a massive difference
There are several easy methods to grind out stats to make you stronk.
1. go to black market. grab free swords. sell them back to him in batches of 1000. since the money cap is 99,999. Then spend it all on body and magic pills (4k each). magic pill gives 100 MAT, 100 MDF, 100 maxMP. Body pill gives 100 AGI, 100 DEF, 100 ATK, and a lot of maxHP. Also use the money to buy monster cores instead of bothering to farm them. (xianxia pills!)
2. very early on you can spend 500 mana to refine mana (+10 to all stats except luck) then sleep to recover mana. repeat as many times as you want. (xianxia secluded cultivation!)
3. you can cast dark restoration (healing spell) out of combat, even if at 100% health. spam it. each time you cast it you get a small amount of agi, mat, mdf, mat, maxMP, maxHP. Also it can trigger demon mode before the start of next battle, so you start in demon mode (temp doubling of maxHP and huge stat boost)
3b. you can cast it in combat. Heck just use command remember to have MC cast it and his dragon cast defend. Then use an autoclick to hold down enter key and walk away for some time. Come back super leveled.
4. Megadeath is great for grinding. Grind some city guards to get the gold to buy it if you do not like exploits. goes real fast with hellfire. (requires buying Death spell first)
5. Sloth rings exponentially increase your XP gains.
Rush acquiring your dragon pet. (from black market). Make it a dark dragon. after a couple of levels it learns miasma. put him on miasma and never look back
megadeath is pretty good against city guards. although only needed if you didn't use the pills
just hold down enter. thanks command remember
The best item in the game is the Greed Earring. First playthrough I just found it in inventory after slaughtering bandits during rescue of nina (dwarf shaper slave). Second playthrough I got it from slaughtering city guards. I think it shows up in inventory due to trigger from either slaughtering enough humans, or opening enough gold pouches, or having enough gold on hand.
There is apparently an entire convoluted questline to learn how to make the dwarf shaper craft them. (that is currently bugged and softlocks you). But I never had need to do it.
Anyways. The greed earring changes your class from [sword mage] to [sword mage sinner]. It increases your gold income from opening pouches by 3.5x. Gives some nice boosts. Sacrifices your head slot (pretty useless), and add 5 ring slots. For a net gain of 4 equipment slots. It also gives you a bunch of awesomely OP magic rings that you can equip into all the ring slots.
Calamity routes makes you massively stronger. At the cost of being somewhat darker
You can hold down ctrl to fast forward dialog. I completely forgot this was a thing when importing my old save. only when I restarted the game did I get told this was a thing