I'd suggest making sure each player gets a roughly equal number of plot hooks related to their backstory/character. So maybe one session is more focused around the oracle and the apocalypse plot, the next session might involve the half-elf's circus approaching her for help with something, the next might have a shady associate from the human rogue's past trying to hunt her down or get her to do them a favor. As long as you keep things relatively balanced, it should be all right even if the apocalypse is a "bigger" feeling plotline.
Also, if you want to make the apocalypse thing a big part of the campaign, maybe find a way to tie the other characters into that plot as well? That way they have a personal stake in it, too.
Hunter or Rogue:
-Bastard child of a wealthy lord or possibly a king, making him a potential heir to the throne or large amount of land. Lots of people may wish him to disappear so someone else may take power. This new King/lord may be an evil person or an evil magical beast pretending to be humanoid.
-Father is related to other character background plots? Evil guy trying to get heir killed, Cult leader trying to capture Oracle, leader of a Thieves Guild, etc.
-Bear was actually Awakened and has been pretending to be a normal bear. Saved from slavery at a circus, he has been tagging along waiting for the right opportunity to reveal his true nature to his friend.
Oracle:
-I wouldn't make the campaign or story about a character for many reasons, avoid doing that. That said, you can still make a quest out of it. For example, instead of making this character THE KEY TO THE APOCOLYPSE, make this character a potential vessel to birth an ancient evil through a profane ritual. Not a world ending evil but something that would definitely kill the character when "born" and potentially kill the rest of the party if they are not specifically prepared for it. A cult could be continuously hunting this character, once discovered, until they successfully capture him. The party can ignore the threats and continue questing other plots or say "enough is enough!" and begin the quest of tracking down and putting an end to this cult.
Thanks both of you for the input :)
I'd suggest making sure each player gets a roughly equal number of plot hooks related to their backstory/character. [...] As long as you keep things relatively balanced, it should be all right even if the apocalypse is a "bigger" feeling plotline.
Also, if you want to make the apocalypse thing a big part of the campaign, maybe find a way to tie the other characters into that plot as well? That way they have a personal stake in it, too.
This is good. My worry was if a "bigger" plotline would make the others feel unnecessary for the world.
I have been thinking of making them a part of the story, but havn't yet been able to think of how to include them
That's a little tricky to say, as it really depends on your players. But if you can figure out a way to tie all of them into the apocalypse, that makes it less the oracle's story and more everyone's story, so I would think that would help a lot.
The tiefling doesn't have to actually be the harbinger of the apocalypse, you could do plenty with a cult that just believes they are. In fact the reverse of this is the backstory for my current character. He's witch (hedge witch/herb witch/some home brew) with the healing patron; he doesn't exactly know who his patron is or if they have a plan for him but a demonic cult firmly believes that he is a chosen one who will heal the Worldwound. My witch, on the other hand views the Worldwound as a lost cause and will happily stay away from it; he is content to sell his abilities as a healer to the highest bidder. This minor detail hasn't stopped him from being hunted and can provide plenty of plot hooks without having to go all apocalyptic.
The only risks of one character being central to the storyline are things like the player not sharing the limelight well, and the ever present threat of character death or player flaking.
The rogue could have been tasked to watch and report on the Tiefling.
As to the Harbinger plotline, if it becomes noisome, prophecies are notorious for being misread. Heck, the ones who are really clued in may have actually branded the tiefling to draw their rivals' attentions away from the one with the true Mark of the Apocalypse.
Or it is discovered that there is a prophecy or belief that in order to bring about the apocalypse the harbinger must also be sacrificed.
Bear was actually Awakened and has been pretending to be a normal bear. Saved from slavery at a circus, he has been tagging along waiting for the right opportunity to reveal his true nature to his friend.Could actually be really interesting, but I think the player is quite attached to her animal companion, so she might become slightly miffed if "taken away" from her
If you like the idea enough and don't want to take it away from her you could allow it to continue to function as her animal companion but boost it's stats as if Awaken was cast when the truth is revealed and speak for it as an NPC. That way, the player actually "gains" something unique and you have many options for background plots. Just be careful with the free will of the bear so it doesn't become a hassle to the player.
Just a suggestion if you wanted to still use this idea but I know some players would prefer their companion to remain a simple animal.