Had the same problem with golem + sentry, tried to undo a few times and the bug kept cropping up in the game, here's a game log and some screens:
https://cdn.discordapp.com/attachments/264784149666201620/265302831454486528/unknown.png
https://cdn.discordapp.com/attachments/264784149666201620/265303220052688896/unknown.png
http://imgur.com/a/1eJ41
https://cdn.discordapp.com/attachments/264784149666201620/265302831454486528/unknown.png
https://cdn.discordapp.com/attachments/264784149666201620/265303220052688896/unknown.png
http://imgur.com/a/1eJ41