Platform, device version and operating system:
PC, Win7, Steam, 5.3.0r25703 GoW version
Screenshot or image:
What you were expecting to happen, and what actually happened:
Small explanation about how I found it out, so this case would be more clear:
Mercy and Rabbit both have the same description in their spells about “allies” part in Russian. When I cast Mercy’s spell, “Cleanse” from her spell works on every troop in my team, Mercy included. When I cast Moon Rabbit’s spell, every other troop will get bonus HP, except Rabbit.
What you were expecting to happen, and what actually happened:
I expected proper translation for Moon Rabbit’s spell: “Трансформирует все синие камни в желтые. Дает по Х ед. жизни всем ОСТАЛЬНЫМ / ДРУГИМ / ИНЫМ / ПРОЧИМ союзникам. Благословляет первого союзника.”
Any word from those 4 words would work and make spell description right and clear.
How often does this happen? When did it begin happening?
Has always been happening. I just didn’t pay attention to it before 
Aaand it almost cost me GW battle.
Steps to make it happen again
Launch GoW client, choose Russian language in settings, check/compare Moon Rabbit and Mercy spell description. “to all allies part” is same in Russian, but completely different in English.