I guess you mean somethin like
"What effect do the golden Cards have?"
The golden Cards, do not have any "special" effects. They work just the same as the normal Cards.
BUT:
- On the map "Golden Grounds" you can only use golden Cards.
- Some Cards are only available as golden Cards. (e.x. Seelenreißer, Blood Demon or Horadric Mage) which offers new tactical builds and synergys between towers/items and thus changing your gameplay.
-You can get golden Cards from the Card Forge. You pay 20 Relics for one random Card. You gain these Relics by doing the daily Quests, available on around 3 am +/- a few hours, depending where your living.
Please be aware that (i guess here) most people in the top 100 Scoreboard (Bonus time) played with at least "Seelenreißer" or even more Legendary Cards. They are powerful so try to get your hands on them =)