Collectible Card Game Headquarters

Describe the Bug:
Game crashes to desktop if any creatures are under Portcullis when it leaves the bf

Which card did behave improperly?
Portcullis

Which update are you using? (date, name)Which type? (duel, gauntlet, sealed deck)
Manalink dev 778ccb5 version - duel

What exactly should be the correct behavior/interaction?
Creatures are returned to the bf

Are any other cards possibly affected by this bug?
[Edit] Maybe related to Helvault bug? https://www.slightlymagic.net/forum/viewtopic.php?f=86&t=22513

Portcullis is supposed to return only the last creature that was exiled by it, right? It is worded "Whenever a creature enters the battlefield, if there are two or more other creatures on the battlefield, exile that creature. Return that card to the battlefield under its owner's control when Portcullis leaves" not worded like others "return the exiled cards to the battlefield under their owners' control."

"That card" refers to a different card each time it triggers. They all get returned, each with a different delayed trigger.