Direct answer: you cannot walk into the Erdtree after Morgott. The entrance is blocked by impenetrable thorns sealed with Radagon’s sigil, and the only thing that destroys them is the Flame of Ruin. That means the real order is: beat Morgott in Leyndell, climb to the Mountaintops, relight the Flame of Ruin, burn the Erdtree, then defeat Maliketh in Crumbling Farum Azula to free the Rune of Death — and only then does the door open.
Why the thorns exist
Queen Marika is imprisoned inside the Erdtree, and after the Shattering someone sealed the entrance against the outside world. The seal is Radagon’s. The Flame of Ruin can burn it away, and burning the Erdtree has always been treated as the first cardinal sin — which is exactly why the game makes you commit to it deliberately rather than stumbling into it.
The order that actually works
- Defeat Morgott in Leyndell, Royal Capital. This is mandatory and it opens the road east.
- Exit east through Leyndell into the Forbidden Lands. The Grand Lift of Rold drops you down; ride out across the ash and up the other side.
- Climb to the Forge of the Giants in the Mountaintops and rekindle the Flame of Ruin.
- Burn the Erdtree. With Melina as your kindling maiden this is the standard route. The Frenzied Flame is an alternative that leads elsewhere.
- Defeat Maliketh, the Black Blade in Crumbling Farum Azula to restore the Rune of Death.
- Return to the Erdtree. The thorns are gone and the entrance is open.
Wrong turns worth knowing
- Assuming the Erdtree opens the moment Morgott falls. It does not. This is the single most common false claim about this part of the game.
- Treating the Grand Lift of Rold as an Altus entrance. It is east of Leyndell and you only reach it through the capital.
- Burning the Erdtree without a plan for Melina. Losing her changes which ending route you are on.
- Skipping Maliketh. The burning alone does not open the door. The Rune of Death has to come back too.
Evidence status
Research-reviewed. The thorn seal, the Flame of Ruin, and the required order of bosses are stated from current game data. Not gameplay-verified — no playthrough capture exists yet.