Grandia's ultimate challenge awaits!
The Savanna is a fairly large and complex area to navigate, so I drew in the path you'll need to follow in order to reach the Tower of Temptation:
You'll have to walk blind through a well-hidden cave in the canyon walls for the last stretch.
Be sure to have plenty of Ultimate, Blue and Gold potions on hand before you go in, because this place is rough! I would also strongly recommend equipping your entire party with non-elemental weapons, as nearly all of the enemies in here are resistant to elemental damage.
Here's that item I wanted to get but missed in the video:
...It's nothing you'd sorely miss, but it is the second-strongest throwing weapon in the game and does extra damage to demonic enemies (which the Tower has plenty of in its later floors).