Hello =)
i just wanted to give you some feedback about how i see your cards:
First off, lets take some other exp gain values.
Painting gives 1.1 exp to the wielder but misses his attack.
Scientist gives exp dependant on his level. Ranging from 0.5-X i think.
Key of Wisdom 3 Exp or what was it?
Then you want to give the same amount of exp to all towers around it. The problem here is, as far as i can see, that you can have a few Iron Mans around, stacking speed items on him and that exp card. I think you would have a full level 99 field (besides Iron Mans) in a couple of rounds after setting them up.
This could be solved by the rarety. Purple/green Card (if you want an set). Still, you can just swap the card to the next Iron Man as soon as the others got a decent level.
The Idea itself is not bad, but i think these Values wont work out at all.
And then there is the "per attack" proc (even an "on hit" might be better if we add a decent miss chance ^^) or just some time Value.
Another Idea might be: Adds 1.5 XP to all Towers in X area every 45s and gives -250% As.
The ability Scales with attack Speed. (so without any AS bonus it would start on 112,5sec which isnt really an issue on an iron man. a few League Boots and its back to basic).
Of course the values can be changed. As for balancing perhaps give the xp to a random tower in range and increase movement speed of enemies hit by 1% and armor by 1 stacking. Make it a 3 card set. . One card has the movement buff, one has the armor and one has the 0 xp gain.
Perhaps reduce tower attack speed by 50% for each tower in range or the xp gained by this set is unaffected by increased xp gain.
I guess I should also clarify that the xp per second is the same with 10s speed and 0.1. Lower xp value when increasing speed.
Perhaps 1xp per hit would be better.
Xp doesn't come from speed of the attacks but the amount of target hit. . Perhaps setting the target to 1 range and only allowing a straight line. Of attack.
Well, here goes my opinion again:
3 Part set on a 5 sec attack ratio. Then you go for a pumpkin and you got 10s (when 5s is the base, with the AS skill you end up on... 8.5-9s?) and gaining the same amount of exp then hittin with 0.1.
Which means you can nearly negate the negative effects :>
Then better go for an aura:
4 Cards in the set, aura which makes enemys move 10% faster, giving +3-5 Armor and about 0.25 exp per minute (or so).
Ant if the tower itself levels, the malus will decrease or the exp will increase slightly.
Still dont think it will be useful at all ^^
Guess this one (if added) will be a pain in Andys ass XD
But here is an Idea which might suit your general idea:
Orb of Clairvoyance:
The orb of Clairvoyance lets you see the movement of your enemys before it happens giving :+0,75exp every X seconds
But your so entangled with seeing the future, that you disturb the Towers around it, giving an aura with -50%as in a 3 Radius.
X OF X (add somethin representing wisdom/knowledge here):
The X of X grants you knowledge of weaknesses of your enemys, granting 1,5 exp every X seconds.
Due to misleading informations creeps around this Card receive +X Armor on a 2 Fields radius.
Key of Wisdom
The Key of Knowledge is unlocking the hidden within one... Effect is already there
Insignia of the knowing:
2 Items : Reducing the Coolodown of the experience gain by 10%
3 Items : Reducing the Cooldown of the experience gain by 20%
Special: If the tower hit by the +exp gain already drank the Potion of Wisdom (Or what the name was with +10 Levels), the amount of EXP gained magnifies by a factor of 2. Only works with a full set!
Would denie Iron man the possibility to be an EXP farm for towers around it :> but well...