I think this cards is totally unbalanced for one good reason : If you don't take it out , you usually lose the game.
I'll get straight to the point : The potential value of this card is unlimited. A Ciri nova will give you 22, Tibor will give you 25 and Echop can give you 25 too. All these card come with huges advantages but have counterparts and can yield you a maximum of 20-25 points.
Eredin , if let alive, even if not buffed, can kill any card with up to 9 power, effectivelly giving +9 point nuke every turn to its user.
So basically, its means that, a non buffed Eredin can give up to 5+ 9+9+9+9, depending on the number of turn played after he is dropped. Which means after two turn he ll already have a value of 20+ points, equivalent to the best gold card in the game, and this without any counterpart to dropping him.
Another points that people disregards often in theorycrafting is that Eredin can be buffed by Wildhunt drakkar. I have done that quite often when the card was released, with Avallach and Eredin leader, you can get up to 5 Drakkar, which means Eredin will come on the board with TEN points +2 armor, making him able to survive almost every basic nuke like Alzur in the game. If you drop a spies before hand, he can't be scorched either. Since he ll kill a hight point target right away, Its means Eredin will have a 20+ point value right off the bat even if he is succesfully locked, for example.
That only for a basic Eredin, but a buffed one with mandrake or any card will usually have 11+ point, resulting in a value of 11+ a maximum of more or less 19 points EACH TURNS (too lazy to do the exact maths, but you get my point). Add resilience to it, game over. Lock can be countered, just as scorch. Imo the only real viable counter to Eredin is mandrake, which instantly remove it from the board and forbid a renew, but really, having to run mandrake and some tutors in EACH deck only to counter a potential Eredin is such a bother, not to mention that sometime you ll still lose to Eredin because you didn't draw your mandrake in time. NO card should have such potential.
Its kills the fun in Arena too, because any deck is susceptible to have it , and there are usually far more gold card in arena deck, and you don't necessarily get the counter to it in your choices. How many game have I won or lost because thanks to this card in Arena, I don't remember.
The best cards to counter it are scorch, lock and mandrake. However, I'v lost several time to this card with deck running Mandrake and lock, because you don't necessarily have it when Imlerith is dropped on the board. Plus the opponent usually have Renew, which diminish grealty the impact of the scorch / nuke card; Not to mention they'll usually drop a spies before so you can't scorch Eredin.
My suggestion is removing the heal+armor bonus on this card, but increasing it base strenght or armor. Also make it invulnerable like werewolf or arachas queen, this way it's cannot be buffed with resilience or point, but it's can't be killed easily by alzur either. A 7 point Eredin will probably kill a couple of 10 point mob, but he ll lose health each time and eventually kill himself during his duel, resulting in a much more controllable point advantage. exemple :
Eredin 7 point : Kill a 10 point mob, stay with 4 point. Then he attack another 10 point mob and deals 4 dmg, then die. Eredin total dmg dealt : 14 which is only one point less than Vanilla Geralt, in an unfarovable situation, so it's really fair.
On the other hand, Eredin would still snowball hard if the enemy doesn't have 8+mob, or if the Eredin user manages to peel down his opponents minions with too much health. But it would still be much easier to deal with.
Also add some mob with armor or invulnerability in every race, or a similar mechanic, so people can defend against nuke deck. Because a nuke deck Eredin would kill hight HP target with scorch , alzur etc, and kill low HP with Eredin each turn which would be totally overkill. We need way to deal with burn deck other than swarming the fields, and atm only Northern realm can really counter that with armor.
