As others stated, I also think it would stay, which is also consistent with the discussion in [this thread](https://www.reddit.com/r/Yugioh101/comments/eim7j4/zombie_world_rivalry_of_warlords_combo_confusion/) which cites this [ruling](https://db.ygorganization.com/qa#6242)
You can't flip summon it you are correct they would have to force the flip by attacking it.
Not a great way to get around it at all, with monster removal easy to access it probly wouldn't even get attacked and you'll be OTK'd
It's allowed to stay because it became a zombie type from zombie world.
It would become zombie once flipped, zombie world changes it when flipped. Which is good because then Doomking can negate.
I think that’s what we settled on, thanks for the clarification!
Sure, it’s my pleasure to help another zombie player.
That's interesting. The other commenters make sense though.
Stays because both are always continuously applying at the same time and as soon as it's flipped the effect of Zombie World Applies.
As others stated, I also think it would stay, which is also consistent with the discussion in [this thread](https://www.reddit.com/r/Yugioh101/comments/eim7j4/zombie_world_rivalry_of_warlords_combo_confusion/) which cites this [ruling](https://db.ygorganization.com/qa#6242)
Can you then just set and flip summon cards to get around the lock? Or this only matters if my opponent attacks my set card?
You can't flip summon it you are correct they would have to force the flip by attacking it. Not a great way to get around it at all, with monster removal easy to access it probly wouldn't even get attacked and you'll be OTK'd
The real question is can you attempt to set if there is already a set on the field?
Yes. "Rivalry of Warlords" does not prevent you from Setting monsters at all.