1, Different ways of attacking.

2, same ish, different pixels. aka, a marketing technique to get more money.

3, Dual Blades have higher DPM and slightly higher hp as well as the ability to rush among other things (they train faster too) Shadowers are somewhat slower but have a bit higher survivability because of meso guard and buy maplestory mesos mastery. Smokescreen is also useful for bossing. Both have insanely high availability XD. And they both compete for the same weapon (dagger) and scrolls etc. XD

Anyway, some other players not agree this, they say, viscious blow is, slower than sb. also, at 2nd job, of course they are still weaker than dbs. at 3rd job it evens out, because honestly BoT is a great mobbing skill, assaulter is probably the quickest strike in the game, and of course pickpocket+sb+meso explosion=epic. also meso guard and that star flare thing give you great survivability. Yet at 4th job, once you get assasinate, imo, shads go much higher in damage

4, from a Shadower's perspective, it was a lot more difficult for us dits to lvl up to Shad, bb of course made exp gain easier but still in my opinion a DB who has the same funding as a Shad will be able to train faster

5, with shield mastery, shadowers become tank. Mastery doubles weapon def. Ex. I have 3.1k def, meso guard, and decent hyper body. =] Shadowers are now fun with fj, dual blade does have higher damage, flashier skills but lack survivalbility, while shadower is more of stable damage and survivalbility. BoT+Assulter+ME is a good combo for soloing zk, but on some bosses like zakum, shadowers can outdmg them / kill zak faster because of meso explosion which is the skill with highest damage when maxed. While Dual blades wait when zak casts that defense thing (wen u hit 1's) shads spam sb+pickpocket and wen zak releases that defense thing we just meso explode. oh and shads hit 4 arms with 4th job skill boomerang step while dualblades i believe still use that 3rd job skill upper stab with final cut to hit multiple arms.
All depends on the situation xd

Im a shadower. so.... pretty much. My opinion is that DB's are fancy and there moves look dope. But are they really stronger then shadowers. i know your attack always depends on your gear. But I am pretty sure shadowers are stronger? Dual blades have an ultimate. But it has cool down. and Shadowers can 1 hko plenty of minor bosses with assassinate. But i think it depends on whatcha like. I’ve had a chief bandit before big bang and i guess it was the right time. because after big bang i never got bored of my char yet. i love my shadower

P.S. Shadowers are very versatile and can survive bosses with there +100% wep and mage defense. Train with the fastest mob attack(Band of Thieves) and are just strait fun now since they got shadow partner and flash jump. My assassinate does 500k+ damage with a full charge. (lvl 1).

Click here to see more maplestory classes comparison with Dual blade.
http://www.gamerluck.com/blog/2011/01/26/why-db-dual-blade-is-better-than-other-class/

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