So, this one is a bit weird.
The eldrazi tokens give mana based on power when destroyed. As defenders, they get the first spot, thus are vulnerable to the flip side of thaumatic compass. When you have at least two creatures out and the tokens are destroyed, the game reorders your creatures so the creature in second spot take the first spot before the destroy trigger activates, thus making the skions grant you mana you shouldn’t get.
//Edited Title - Tombstone