Edit2:
After a second more thorough look through the forum this is the chimera/bravery bug in the known bug list here:
http://elementscommunity.org/forum/index.php/topic,39012.0.html [nofollow]I did try to locate this bug before posting it but somehow missed that one. I apologize for the inconvenience.
Mods feel free to delete this thread. Thanks.
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I tested this multiple times to verify.
Playing in Arena with a fully upped deck. If I had multiple Singularities in play (from Supernovas), if I cast Shard of Bravery and one of the cards drawn was an upgraded Chimera, the Singularities in play got combined into a Chimera.
I only have 1 Chimera in the deck, and it would be left still sitting in my hand after the in-play Singularities combined. So I am quite sure it wasn't the result of an erroneous click where I accidentially cast the Chimera in my hand.
I don't know if this works with unupgraded cards. I also don't know if it works when there is just 1 Singularity in play, since that scenario did not occur when I tested to verify.
Edit: adding screenshots.
Deck used:
Non-error state, drew Chimera as normal:
Note that drawing a Chimera via a Sundial didn't cause the bug.
Error state, see Chimera in play + in hand: