completely stuck finding the hearts of beasts

[MadAsAHatter]

and there are no useful walkthroughs online yet. I finished the first three worlds and after the fight in the core, some door should have opened in the worlds. I didn't find a single one of them, at least not open and I'm completely stuck. Where would be the access to the new area in the forest world for example?

[Mr. Delval]

For the one on Arden fast travel to "The Tribunal Of Souls" obelisk it is right behind where you spawn.

In terms of the Apexion one fast travel to the "Citadel Gates" Obelisk it is the large doors behind you, they will open once you approach them

For the Viridian travel to "The Temple Grounds" Obelisk and then take the path up the hill to the left, you will pass by a closed door and then be given the option of left / right. Take the left path towards the large enemies with the LMGs the door is at the end of that path.

[MadAsAHatter]

The two doors behind the obelisks didn't open at first. I had to restart the game twice, then the 'open door' appeared. Thanks

[MadAsAHatter]

... now my confusion is even worse. I found two of the heart fragments (strong guy and the poison tree guy) and I have no clue where the last one is. Are the three worlds connected by portals? Because I think I started one one plame and ended up in the lava world which is a different planet.

[MadAsAHatter]

Oh, boy, this game is confusing. Looks like I traveled between planets, from Arden to Veridan.