Blade's Nightstalker not stealing?

I had a match when the enemy’s strongest color were purple and the Nightstalker ability refused to steal it.

Can someone confirm this or did I imagine it.

Thanks in advance

It may have been an example of this bug. If so, it may have been stealing from another color.

Ok it’s a old bug. Well I guess Blade’s power isn’t that badly effected but BP’s power can really screw you over.