This bug happened twice in 24h.
I fought against Ai5. First played two nightfalls and than a eclipse. My upped Bonedragon gained 2/2 overall. I
can't reproduce this.
I have replicated the bug. It was another fight against Ai5. First it played a Nightfall than two Thunderstroms, after it played a eclipse the hp from Bonedragon went to 5. Maybe your opponent must play Nightfall and Eclipse, because I tried in the trainer by myself and it didn't work.
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http://imageplay.net/)
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http://imageplay.net/)
Btw: How can I get the picture big?
Edit: adding better pictures