Now this will be a bit Controversial so i already know i can expect a -1 from Haron, Gulere, Astor, Bmw (Just kidding love you guys)
I had 2 rough ideas about Voodoo cards.
1. Have different tiers of voodoo cards.
All obtainable from Packs, presents. All tiers create a new card, So they can all be auctioned and sold
Example:
20% to obtain Broken : either 50% chance to fail usage or 50% effect
70% to obtain Normal: Regular as we have it now
9% to obtain Supreme: 2x the effect, reward or duration of the card
1% to obtain Mythic: 4x the effect, reward or duration of the card (60% failure getting rid of it maybe)
2nd Idea, In combination with idea 1
Being able to upgrade cards to higher qualities of the same card
Example:
2x broken Mindbar + turns+ gold, makes a Normal Mindbar (90% success, failure makes you loose one card and all turns+ gold used in upgrade)
4 Normal Mindbar + Turns + gold, makes Supreme Mindbar (80% success, failure makes you loose one card and all turns + gold used in upgrade)
3 Supreme Mindbar+ Turns + gold, makes Mythic Mindbar (70% success, failure makes you loose one card and all turns + gold used in upgrade)
-1