Strong Lubricant Oil

The Strong Lubricant Oil is a key item in Xenoblade Chronicles. It can be obtained from Bright Wisps. It has no use and was likely planned to be used for an alternate route for the Power Up!, as completing said quest consumes this item.

Since the Bright Wisp that drops the Strong Lubricant Oil respawns as long as the quest is active, it is possible to collect multiple units of oil, up to the inventory stack limit of 99. If the enemy is then defeated again, the player cannot take another copy of the item due to the stack limit, but they also cannot discard an existing copy (since key items cannot be discarded), nor can they choose to skip obtaining the new copy (since key items must be collected). This softlocks the game on the item pickup menu, forcing the player to reset or shut down the console. This was not fixed in the Definitive Edition.