Had a similar thing yesterday in spider, did 7 battles and only won 1 accessory but got 8 shards and 2 brews. Rng I don't think so. You play certain battles for specific rewards but end up with everything but what you play for.

I think you have been a bit unlucky there. It often happens that when I want lesser potions, I get greater ones and vice versa. RNG can be cruel.

Wouldn't mind blue shards though.

Repeat after me. Sample size. Saaaample siiiiiiizeeeeee.

I have to agree with kramaswarmy.kr

if you track 10 runs, in any content, the odds are good that you will feel like either a big winner or a big loser.

if you track 100 runs you may feel a bit lucky or unlucky.

if you track 1000 runs, most likely you'll feel perfectly average.

fyi and fwiw, there is a chart on ayumylove that gives the drop rates for each stage.  I can't  vouch for its accuracy, but it does seem to be close enough.  Just go there and search "loot"

  Dave, I feel your pain.  

There's nothing like queuing that lvl 20 - 25 encounter for the sweet 5* - 6* loot... pushing your team to it's limit for 10 - 15 minutes on manual... the excitement when you get that run saving proc or you crit at just the right moment. 

Watching the last 1% of the boss' health bar disappear as the foul beast falls to the ground!!! 

Your team turns around... does their flourish animation!!! VICTORY!!!!  

Tell him what he's won Alex!!!! 

3 Mystery shards... to go with the 2500 others you already have... that you can't even sell and could pick up in the market for 15K silver...