For Mirror Box, that rule is the legendary rule that says you're only allowed one copy of a legendary creature card on your battlefield at the same time
The only reason Traptrix Pinguicula isnt higher up on the list is because she really doesnt do that much on her own, she is great in a Traptrix deck but doesnt really shine all that bright in every situation
Maybe you consistently churn out a ton of mana to spend on huge spells as games run long into the night, but youd rather it be a little more guaranteed than it is when it comes to Magisters effect
Finally, the set includes a selection of 4 special Energy Cards, with each one featuring one of the stars on the face
item lock on a Stage 1, and it was very, very strong
King of the Ashened City X DARK Level 8 [ PyroEffect ] ATK 1400 DEF 2700 If "Obsidim, the Ashened City" is in the Field Zone, you can Special Summon this card (from your hand)