i've played MW 5 times, 3 times i've played  WIzard and always won, then last 2 games i;ve played Beastmaster and lost both of them. After those 2 games as a BM I'm also not convinced to use  swarm attack with many 1lvl creatures because they die before they do any harm. Probably I played them wrong :/Also unfortunatelly i don't have card Galalador which could change MUCH MUCH my situation. I realized that i have no creature with ranged attack  and only on weak with Ethreal attack which is very bad. Galador will be very useful, but i cannot get it :/ frustrating....

thanks for concern. i think i understand why DB will hit it's owner according to rules.

X - attacker / has Damage Barrier
Y - defender/ X's enemy / has Reverse Attack

X makes melee attack against Y

codex (last pages in roolbook) says:

Damage Barrier
A damage barrier surrounds an object and makes an
automatic attack against each enemy which makes
a melee attack against the object it surrounds.

so X is surrounded by the damage barrier which will do automatic attack against X's enemy (Y) if Y makes melee attack. And only reason Y isn't hit by DB is that the rules didn't say that he becomes an attacker after using RA. Rules only says he became a controller of the attack.[strike] I think it's not exactly how it should be. If i control attack and reverse it to my opponent i should be an attacker from that moment.[/strike]

hmm.... actually i've changed my mind that's funny. i tried to imagine that situation, and it's not that silly as i thought. just because DB work for melee attack only. So X try to hit Y with for example sword but it's reversed against him and he hits himself. DB doesn't have it's own intelligence and hit back creature which attacked object which DB is defending. in that situation it's same creature
before i always was imaging some thunderbolts flying from X to Y than reverse from Y to X, and that's why i
rather treat Y an a new attacker. I feel calm now

thanks a lot for explanation.

PS.
what would happen if X also had Reverse Attack?

"Poisen blood is crucial on the priestess. So is a nullify to protect it. I waited until late game, on a turn he activiated her first and had no hidden enchantments on her. I then dropped both on her. From then on, I made sure to have another nullify in hand incase he tried to clear her poisened blood off, and thus used up my nullify. He did, so I reapplied nullify to keep her health down"

Actually, I think you played wrong. If you reveal Poisoned blood on opponent mage, you can't protect it from Dispel by using Nullify enchantment. And here is why not:

If i'm Prietess (or other Mage) and i use Dispel incantation (Destroy the target. X = total mana cost of target enchantment (hidden plus reveal cost).) to remove Poisoned blood it won't trigger Nullify, because target of this spell is not Creature but Revealed Enchantment.

Nullify works:
When this creature is targeted by an incantation or enchantment spell controlled by an opponent, you must reveal Nullify during the Counter Spell Step. That spell is countered. Then, destroy Nullify.

You can try to block Dispel incantation by Jinx enchantment though...