A world building / plotting trope that uses the existence of magic in a setting to explain away any part of the setting that seems incongruent.
This can be legitimate - functional magic must be expected to make signifcant changes to all aspects of technology and may well be behind some aspects of the setting - indeed it might even be discordant if it wasn't. It's also legitimate if that particular element is meant to be discordant and even makes people in setting wonder.
This trope only really applies when the use of "it's magic" is used to cover up continuity errors, research failures and other unacceptable breaks in reality caused by lack of thought or effort on behalf of the author.
Where magic is not generally a major force in the setting, but is still invoked for these purposes, the trope may be stretched to A Wizard Did It And Then Ran Away.
Game and Story Use
- The Wizard who Did It could make in interesting high-level NPC.
- Why is there some wizard messing with reality? Curiosity? Idealism? To let in some eldritch abomination?
- Again, some incongruent world elements could be legitimately explained by "a wizard did it" - for example "why is the bestiary full of monsters that seem designed purely to trap dungeon-delvers1?" "A wizard did it - specifically, these monsters are purpose built biothaumatological security devices which, in some pre-lapsarian society may have been sold from a catalogue".
- On the other hand, it can be over invoked - witness D&D's owlbear - allegedly so outlandish that it was obviously a mad wizard's work. Except, of course, that real life has given us a beaked (or at least billed), egg-laying mammal with venomous spikes in its butt, so why shouldn't a fantasy world have a beaked, egg laying mammal that just happens to be a top carnivore? It doesn't literally need to be a cross between a bear and an owl, just look enough like one to make people note the resemblance.