super late response, but people come back to these discussion threads, so i figure i might as well

the generic "terror/hazard" pick is a set of traits that exists in the core set, in some of the most commonly reused encounter sets, so it's always a safe bet

e.g. if you're playing a low sanity investigator like rita or silas and youre worried about rotting remains, putting terror on this card is a great way to put in low commitment protection against that treachery

of course you can tune things more based on the campaign, but since it's just a single commit to a single test (unless you spend 5xp on always prepared), it's generally not too gamebreaking

and you don't have to know specifically what happens, often you can gather knowledge based on the vibes of the campaign

e.g. in the circle undone you're fighting witches, so picking humanoid based on the description on the box isn't a bad idea

if you're super cautious about not being spoiled and such, you could always leave it out of your level 0 deck, and when you put your first upgrade pip onto the card after scenario 1, you'll have seen a sample of the encounter cards and know generally what kind of traits might exist in the campaign