What does this glowing thing mean?

[Skyld]

Once, after winning an online battle, after viewing the results, I went to select the pack of cards to win. I selected blue, and the first card I got was a slicer. "Fair enough" I thought, but then, as I was about to press A (or maybe I had already pressed it, I don't know) the card began to glow and loads of white particles (like the ones that appear when you press A during a loading screen) flooded the screen and went into the slicer card, the screen flashed white, and then it went back to normal. The slicer was there, unchanged, yet at the bottom it said something along the lines of "Probability range increased from 10.5% to 55%". Anyway, after that, I went to look through my cards, but I could not see any special slicer or anything like that.

Can somebody please tell me what it means, and what difference it makes?

[Ivan]

Sometimes cards can transform into rarer ones. I guess in this case I guess it didn't

[Serpent7]

Yeah, the probability thingy means that the probability of getting a rarer card changed from 10.5% to 55%, but that means there's still a 45% chance of it NOT changing. Unlucky, maybe next time :'(