Legendary Pokemon Won't Spawn

I know hidden grottos can be broken and quit producing pokemon, but is it possible for this to happen to legendary spawns as well? Despite KO’ing both Volcanion and Heatran at the first encounter, I can’t get Heatran to pop up in fiery cave whether I finish the magma stone quest or not. I was able to capture Volcanion no problem, but Heatran simply will not show up despite being in the correct area.

I also cannot get landorus to show up despite walking through the rocks the correct way while having both tornadus and thundurus in my party. I haven’t caught the thundurus in the safari zone on my file yet. Does that somehow affect whether landorus will show up or not depending on whether i’ve completed that part first?

Do you have heatran registered in your dex? Heatran and Volcanion, similarly to the legendary beasts, spawn until they are registered to your pokedex.

So basically you have to shiny hunt volcanion/heatran at full odds? I thought it was only the beasts and giratina that you couldn’t shiny hunt w/ the charm… but yeah I registered heatran as I thought i’d be able to get it w/ shiny charm odds

I supose you meant Cresselia.

Have you tried playing in a previous version?,

I played most of the game in version 1.2.5, and never had the problem of Landorus not apperaring.

Your story made me remember a bad memory, while playnig the game i got a Heatran in a trade, and after doing a test battle in the Infernal Dungeon i went to the locations where Volcanion and Heatran are suposed to show up. I then realized that my only chance to get a shiny Heatran was that double battle.

You can actually find cresselia even if it’s registered in your dex.

Really?

I don´t remeber where i read that she worked the same way as the other roamers.