So I had a discussion with a friend, because the way a buddy played Absolute Zero is that he used a power to deal himself 1 fire damage, which was buffed by my legacy, he took (for the sake of the example), 3 damage after buffs, then took that damage and redirected it, adding my buffs again for a total of 5. Should he get the buffs twice?
In the interest of generalising this answer, "redirecting damage" and "dealing damage" are distinctly different. Redirected damage still has its original source dealing that damage. Redirected damage is not buffed when redirected.
If its more helpful it was Isothemic Transducer, which I cannot recall if the damage was redirected, or "done again"
It's redirected damage because the card states that whenever Zero takes fire damage he deals a target that much cold damage. Legacy's damage would increase the fire damage Zero does to himself but it doesn't apply to the redirected damage since it's coming from the same source. If you have Focused Apertures, that would increase the redirected damage because it specifically increases cold damage done by zero and so when fire gets converted to cold that bonus now applies.
Absolute Zero does not redirect damage. Cards which redirect specifically say 'redirect'.
Isothermic Transducer makes it so when Absolute Zero is hurt by fire damage, he then deals a new instance of damage where the base strength is the amount his HP went down. This new damage is then boosted like any other damage, so Absolute Zero would deal out 5 cold damage (assuming he was getting a +2 to each damage). Using Thermal Shokwave with Isothermic Transducer can end up getting the boost applied three times.
At first it can seem like Absolute Zero is cheating the rules somehow, but his abilities are built around taking advantage of how this works.
Your buddy played Absolute Zero correctly.
There is no redirection here. If Absolute Zero is deal 3 fire damage, he then initiates a new attack of 3 cold damage. If Legacy has used the Galvanize power and Absolute Zero has Focused Apertures, then Absolute Zero would deal some target 5 cold damage.
That makes sense.
Yeah, it's how you can heal yourself from using your innate power as long as you have any kind of buff out that only affects your cold damage. I was playing a game the other day whre I was Ab'Zero and my friend was Visionary and we were against Plague Rat. I ended up with Infection and both copes of Twist the Ether on me. This meant that at the start of my turn, I had to deal myself 1 irreducible toxic damage (from Infection). However, as it was myself dealing the damage, Twist the Ether could apply. So, while you can't reduce irreducible damage (well, obviously ;)), it cam be increased. So we did that. Twice (once for each Twist card). And converted the damage type to cold. And I had Focused Apertures out. And the Nul-Point Calibration Unit (of course). So I dealt myself four cold damage automatically at the start of my turn, which meant I healed for that much. And that was before I'd even had a chance to play a card :D.
I could then, if I chose, nuke myself with my innate power for fire damage (3 damage - 1 base +2 for both Twists), and then nuke myself again with the resultant cold damage from my Isothermic Transducer (3 base because that's how much fire damage I dealt, +1 for Apertures, +2 for Twists) to heal for six damage. On the final turn, I actually dealt this six damage to Rat because he only had about 3hp left. And that was the only reason I didn't finished that fight on max hp :D.
Thinking back I'm pretty sure that's how my group played with Zero. It's been a while since I played with him, though.
If by "the rules" you mean "laws of thermodynamics" (as discussed on the card in question).
Side Question but still about Absolute Zero
1) If a card makes him invulverable to fire damage, does it still count as dealth damage? So he can redirect it?
2) If he is dealth 1 fire damage, and the card that reduces 1 fire damage to zero. Can he stil redirect that 0 damage to hit himself to heal 1? As Cryo Chamber means cold damge deal 1 more. Or can he deal 0+1 damage if he has Focused Apparatus?
You should not use the term redirect to refer to the ability given by Isothermic Transducer, for the same reason you shouldn't use the term "skipping your turn to draw two cards." With Isothermic Transducer, when Absolute Zero takes actual fire damage (and his HP is reduced as a result), he will then deal a target cold damage of equal amount. It has also been stated that if damage is reduced to zero or HP is not reduced in any way from the damage, then damage was never dealt.