I agree that shards are not good about theme. I would like to see them replaced by normal cards, because art and theme is a joke. Shard of... Shard of Readiness? Really? Shard of Freedom sounds like something you get so your wife wont bother if you return to your home completelly drunk at 4 am. Lol.
About the mechanics, I would also suggest some changes:
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>>> stall, and now evasion to immortal creatures? I would change it completelly. If a shard is a creature buff, to me it wouldnt be aether, and even less avaliable to immortal creatures with a defense evasion. How about a big effect that lasts 1 turn instead? Like, "For next turn, all your creatures deal spell damage (or all enemy creatures are in a time bubble, maybe, something that affect a major part of the game table, as a effect of universes clash), and your opponent is silenced"?
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>>> another one that is very very bad. Get some of these and creatures do bigger damage, evade shields and are immune to CC. Sounds like the aether one, buff + evasion + immunity (well, these have global effects, but are vulnerable to PC). How about "target creature gains +3/+1, airborne and sniper skill (cost in its element quanta)"?
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>>> I dont see it as so UP as people say. The real problem is, if you have creatures damaging the opponent and he has no healing, the shard does nothing. It could be something like: "Players and creatures cant be healed. Deals 2 damage to opponent." However, this fits better to Fire theme, I think.
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>>> a shard of Death that does healing, keeping you alive? In a OP way? I would prefer a strong single CC that Death doesnt have (except for Virus, which is weak, vulnerable itself, and is more important to trigger death effects). Like: "target creature receives -2/-3, is poisoned and lobotomized"?
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>>> I see no problem with the current Shard of Integrity. Of course, if we were going to revamp the shards, this card needs to be redone. Maybe something that creates a Golem based on pillars, or permanents, removed from your hand?
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>>> although Im not really claiming it, I feel myself somewhat creator of this card, because of
this. Its one of the best, people say. Although I dont see an entropy card being a positive side anymore. Its a card designed for rainbows (no one will use in a mono or duo, because most times you get 2 useless cards), and now it consumes the entropy quanta. I would just change that.
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>>> good one, too. Wouldnt change its effect although it could fit other elements better.
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>>> this was OP, everyone knows. 3 free PC and a Black Hole. Combined with Gravity Force, even worse. People say its balanced now. I disagree. Maybe 2 PC were good enough. Or HP could decrease if you use the skill, so it wouldnt be recharged by Gravity Force, or wouldnt become that juicy target for catapult or acceleration. Initial HP could of course be lower. Maybe like 0/9, and getting -4 for each use. You would still have 1 use most cases, but the using it would be risky.
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>>> surely, doesnt deserve to be a rare card. I think, Life already has heal from permanents (Bonds) and spells (Heal), why not having a creature with heal? And low health, and like 3 cost to use skill (otherwise mitosis would be a pain). But of course, wouldnt be a rare. We would need design another rare.
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>>> I think its ok, but could use another type of effect too. Like a defensive boost for you and your creatures. Now, it looks like the Heal spell.
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>>> the effect is cool, but could be at other elements. Like light (I think about this as an inspiration of how to do things more efficiently, or a gift from heavens, lol). Deck acceleration is already a theme of Time, the Fire Shard could fit in here, and you could draw 1 card more than the opponent.
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>>> I like the card effect. Growing creatures in exchange of not attacking looks good to me.
These are just some suggestions I think could improve the game. But like people said, I dont really think its even worthy discussing unless Zanz wants to change something, which is hard to know.
Its his game and he always does what he decides, not really caring about the community opinion. Look at the Card Ideas forum. How many interesting ideas lying there to never see the light outside. Some have been voted and advance to 3rd stage, and then he comes and decides to add a card of any stage (why the stages, why the voting?). Sincerely, hes not taking elements developments seriously (for any reason, maybe because he cant), and I dont see all the community effort is worthy. He can create a competition about designing shards, get tons of suggestions, ignore them all and design a stupid Shard of Wisdom. In fact, was this shard invasion really wanted by the community? He started with an idea for SoSac (which would last for 5 turns if Im correct) and decided that every element would have a shard, simple as that. He disappears for like 1 year, and when he returns hundreds of card ideas later, he adds 3 cards (2 of them having the same coding). Where are the new quests? Or new content? Nothing was added after the Arena. When were the last FGs (or even AI3 decks) added? Wait a moment, I will check: hmmm, late 2010.
I really doubt he have a big revenue with the game, and seriously, he doesnt deserve it. Sincerely, this game will never be as good as it could because of him. Lack of updates, lack of caring about the community, poorly designed cards, cards nerfed just because are used... do you think he will even read these lines? I seriously doubt it. So, yeah, shards will change... WHEN, and IF he feels like that, period. Although I would like it.