Ugin's Nexus Death Question

[ISBPathfinder]

In short does Gandalf the White allow a dying Ugin's Nexus to turn into two turns or is it some weird Academy Rector (I am aware rector doesn't work with gandolf but it requires itself to be exiled to trigger which stops any sort of duplication of its effect) kind of weird stuff with this? Its different wording than the rector but I am still a bit confused on if it works or not.

[void_nothing]

No, but not because it's got an "If you do" clause. There's just no interaction at all here: Gandalf the White causes triggered abilities to trigger again. Ugin's Nexus has a replacement effect, which is a static ability, not a triggered ability. It has "If... instead..." instead of "When".

[ISBPathfinder]

@void_nothing just to clarify, Gandalf the White still works on death triggers right? This is just a narrow case of Nexus not being a death trigger event and a replacement for death trigger if I understand correctly. I am just verifying that Gandalf isn't narrowing in on "leaves the battlefield" like Reveillark and works in general on death triggers too.

[void_nothing]

Yes, dying is one event in the broader category of "leaving the battlefield". So generally speaking abilities in the form "When this permanent is put into a graveyard from the battlefield" or "When this creature dies" will trigger an additional time with GtW out, as long as the permanent entering or leaving is legendary or an artifact.