I have this information from here:
http://neoseeker.com/resourcelink.html?rlid=164454&rid=152266=========================================
3 What Affects RNG [~WAR]
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You can treat the RNG as a list of numbers (this list is pre-made and fixed
within the PS2 hardware). Basically, the RNG shifts to the next number after
each use. For example, let's assume that the list of RNG is [0.100, 0.200,
0.300, ...]. So the first time you call RNG, it returns 0.100. And the second
time you call it, it returns 0.200, and so on. So each time the game "fetch" a
random number from RNG, the next number will be changed.
Now let's see in FF12 IZJS, when will the game fetch a random number:
- Each time you attack (the damage is random within a range)
- Each time you take damage (the damage is random within a range)
- Each time a foe actions (the action is random based on AI)
- Each time a foe is respanwed (monster's stats is random within a range)
- Each time you open a repeatable chest (the treasure is random)
- Each time a chest is respawned (this excludes all 100%-appear chest)
- Each time you save (There's no random part in saving but it do affect RNG)
- Each time you teleport (Same as above)
- Each time you get or get rid of a status (Positive & Nagetive)
- Each time a foe or a NPC moves (They walk randomly within a range)
- Other events that contain random part
All events above will change the RNG and make it hard to predict. Now I can
answer the question before: Before you open the chest, there must be many
random events occurred (such as foe respawn, attack or teleport) so each time
you open the chest, the RNG is different, that's why you get different
treasures.
But, nice if this is wrong, make it a little easier to obtain some things. Besides, is there any RNG Method to obtain Seitengrate?