Barrier causing creatures to take more damage

ver 0.0.39

When a creature has Barrier, it takes more damage.
Screenshots below.

https://imgur.com/BxYnda5 - 1st Spell with Barrier
https://imgur.com/7utuJy2 - 2nd Spell without Barrier
https://imgur.com/roJe1z7 - 3rd Spell without Barrier

My same creature casting the same spell against the same enemy creature. If anything, the expected damage of the second and third spells should be higher than the 1st, since it should have lost Defense from the 1st spell (and a few other Shellburst I cast in between).