Collectible Card Game Headquarters

Describe the Bug:
When multiple copies of Ivory Guardians are on the battlefield while the opponent controls a nontoken red permanent, each copy of Ivory Guardians gets +1/+1.

Which card did behave improperly ?
Ivory Guardians

Which update are you using?(date,name)Which type(Duel,Gauntlet,Sealed Deck)
CoRM15 mini, duel

What exactly should be the correct behavior/interaction ?
When multiple copies of Ivory Guardians are on the battlefield while the opponent controls a nontoken red permanent, each copy of Ivory Guardians gets +1/+1 for each copy of Ivory Guardians on the battlefield..

Are any other cards possibly affected by this bug ?
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Fixed in 557a611

Cumulative effect is granted, but it is granted while Ivory Guardians is on the stack

Fixed in fe8782c