Tried to level up a barbarian deserter on level 20 on second tier to third tier. When picking a unit to merge suddenly something changed. I tried to look up for my second tier deserter and found out that it is already third tier with same 20 th level  which is anice and welcome surprise but still i suppose it is an uni tended behaviour. I doubt this bug is easily reroducible, still, if such reports are already present may be you would fi d so e system behind it.

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