Just had an arena match where 2 of my 4 champions had Brimstone on them simultaneously. Never seen this before. Brimstone says only one can be active at a time.

Anyone else seen this and know how it happens? The other team didn't attack, the Brimstones were placed from me attacking them (probably some sort of reflect mechanic).

Ragash used A2 Fur Typhoon and got Brimstone on himself that then activated. Gnishak went second and his A3 also caused him to get a Brimstone debuff which then also triggered (while Ragash still had 1 turn left on his current Brimstone Debuff). Other team didn't have Brimstone but my Ragash and Gnishak both do so I'm guessing their own Brimstone got transferred back onto them?

EDIT: Added picture of team I faced 

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