Try to group foes together in order to charge youy Rage faster. It’s a thick red meter just under your HP, MP, and Exp bars in the top left. When your Rage meter is full from getting consecutive hits all attacks will do more damage. This is the best time to use MP against large opponents.
The absolute best equipment you can find is from Rare Box drops in Boss Raids. Items can have level 40+ stats without any requirement to equip.
Around level 27 i found a Rare Weapons Box from a boss drop in Boss Rush on Medium Lv. 16-30. Inside I found a Rare Strong Bow of Death with 795-903 Attack, HP+ 50, MP+ 100, CRI DMG +68.7%, CRI Rate +8.5% and 7 Elite Stone upgrade slots. The bow does not have any level requirement to wear and be about level 40-50 if it did. This weapon makes single player much easier from stage 25 on.
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Dark Avenger Walkthrough
Stage – Info
5 – This boss only has 3 attacks. If you get to close she will spray lighting a medium distance in front of her, to dodge run away from her or behind her. The second move is long range 2 missile burst. lastly she will teleport away from your Ultimate moves unless you can catch her off guard.
10 – Using knock back moves after boss melee attacks towards you will cause him to move back make the next combo attacks continue, but are out of reach. When anticipated this will let ranged fighters stand their ground and continue firing. You will always find a HP potion here.
15 – Boss will teleport away when you try to use Ultimate moves so you have to catch her during an attack animation.
20 – Same as 10, but all enemies have better stats. For quickest kill just Rage then hit him with everything you got.
25 – Boss is a magic user that attacks large areas from a distance. Best to kill her quickly as she can put out a lot of damage in a short time.
30 – This boss will jump on you from very far away, run fast in any direction when you see his location ring flying towards you. This stage will always drop 1 HP potion. If you can complete this area fast it’s a great gold farming spot.