Tbf, the odds to get 4 in a row is small, but looking at it from the perspective of singular draws (because that’s what she did), the odds to get an ace in each draw is not as small.
If anything the probability of rare item drops is probably smaller than getting an ace in a single draw.
Edit:
Mathematically, assuming the cards they use is what we know:
There are 52 cards, 6 has been used so 46 left in deck.
Luce’s first draw would be 4/46 to get an ace.
Second draw would be 3/45
3rd would be 2/44
4th would be 1/43
The combined odds for 4 cards in a row would be: 4/46 * 3/45 * 2/44 * 1/43 = 0.0061%
Now this is quite small.
However, her worst odds for a single draw in order to get an ace is only 1/43 = 2.32%
This isn’t that far from a rare drop in some games, even some gatcha games probably has worse probabilities.
