Caution These Bugs Appear Only Online
Nibelung's Treasure - This card you choose the card instead of your opponent and it is get activated at once
Magic Removal Virus Cannon - After Activating this card opponent life didn't decreased to 100
The bug is that the text is the old "custom text" and has not yet been updated to the correct text.

Hopefully we can fix this in the next update.
Not bugs as all. A look at the Yugioh wikia will tell you that those cards had different effects. The real anime effect of Nibelung's Treasure lets YOU pick which spell card gets activated on your opponents side of the field. Magic Removal Virus Cannon does not cost LP.

They were changed because the person who added them thought they were too OP, but since most people dislike nerfed cards they were returned to their original effect. Although they have yet to have their text fixed T_T

The only actual bug is Nibelung's Treasure where if you activate a normal spell card on your opponents field, or an equip card, YOU get the benefit instead of your opponent. THAT bug needs to be fixed asap.

There are two other cards fixed in such a manner without the text being fixed.

Btw the actual anime effect is still printed correctly on the actual card.