If you learn your second leader skill, you may no longer go back to your first leader skill. Learning your third leader skill allows you to switch between only the second and third skill
This bug has been fixed and can now reactivate your first leader skill
Slinger Famirae's second leader skill is incorrectly named Heal Resist, which is possessed by Lancer Figaro. The heroes' leader skill pattern and its description indicates it should be named Support Resist. (more of a typo than a bug)
The Passive Skill 'Will to Survive' claims to increase the Defense by a percentage (30% for level 1), but actually reduces total damage by that amount (30 points for level 1). (Pandora's Box boss in the Energy Temple, who has level 5 'Will to Survive', has 38 total damage reduced instead of 38% increased defense when close to death).
Sometimes randomly, purchases of stars or bundles do not go through (it is unsure what causes these, only a few occurrences have been reported.)
The item Alexander's Power does not remove all buffs and debuffs from both parties. Some of these include your own "Increased chance to be targeted" buff (Provokes/Defender bursts) and Health Regen effects. This might be intended to favor the player, but since the item's purpose appears to be "to equalize the field", it is being reported here as a bug.
Times are 2 hours ahead in PDT. The "new day" in this game starts 10PM PDT, and events stated to start at 7AM PDT on the official forums actually start 5AM PDT. Another way of thinking about it is everything runs on CDT.