I'm not the best at balancing, so I won't but...
1)These cards are trying to do far too many things at once. I understand your desire for each card to be unique, but don't force the two versions in one idea, this would be much better as 2 separate ideas.
2)Why would I possibly want to use the un-upgraded over Unstable Gas? This is a trio, much harder to pull off, and it has a maintenance cost. Sure after turn 2 it becomes more powerful than UG, but at turn 2 I can detonate my UG(to clarify this should start with 0 counters, starting with 1 counter means you're skipping over the maintenance cost you implemented for turn 1) Even if I wanted to let it grow over several turns, it's just that much weaker to PC.
3)Tables and cards don't much up(active vol skill cost).
4)You leave a whole lot of implications to your notes section- in other words- the card is potentially overly complex, think Occam's Razor: Simpler is often better.
5)Active Volcano is OP-
5a)Fire Bolt is often enough to kill a creature-having it be reusable on its own, even as a chance-is slightly too powerful.
5b)The activated effect is essentially a slightly weakened Rain of Fire... at a third of the cost... The self delaying mechanic does nothing to balance it here. It would have to cost 4 to be comparable to Rain of Fire
1) I like the fact of having 2 different mechanics in one card and i agree that ETG rarely have cards who works in a total different way normal/upgraded, but i also like to keep the theme.
Being this also my very first card it's a bit against-standars i admit it and i'll probably get more focused on 1 strategy/mechanic when doing a new one, but i think this two biggie are gonna proceed togheter(for now).
2)The 1 starting counter it's accorded to the theme, 'cause no counter first turn=Volcano Inactive not quiet and also, you too said that: there will be no reasons to use thig instead of UG if 0 counters start, so i maked it having 1 starting counter but harder to pul off, you also said that, self explanatory.
I see this being that much weaker to pc if just protect arctifact
...
3)fixed.
4)Overly complex? Does it is written on the card that when you steal a cloak counters restart? Or when you steal a sundial, same thing.Basically the steal thing and the 1 counter start are the only things that you have to discover by testing or going on the forum, the immortal stuff is kinda clever don't you think?UG doesn't say that its damage is reflected by anti spell shield.
5)
5a)Having the chance to might throw a fire bolt at someone for 5
and the chance of the bolt generator being destroyed or stolen instead of the normal bolt bam-direct damge spell seems a good point to say it is slightly too powerful?
5b)It also hits and delays YOUR creatures.
Ty for the feedback anyway