Comet Of Doom has these relationships to other tropes:

parents kids shares a parent with:
Portent Of Doom
parent child
Portent Of DoomBad Moon Rising
''Flying Dutchman
''For Doom The Bell Tolls
''Our Banshees Are Louder
''Red Sky Take Warning
''Signs Of The End Times
''Tarot Troubles
You'll need to Get Known if you want to add or modify these relationships.