chaos form yugioh card Yu-Gi-Oh! Wiki Spellcaster/Ritual/Effect Yu-Gi-Oh - Illusion of Chaos

As a matter of fact Demonic Consultation is only legal in Vintage these days, and it's on the restricted list

SE Secret Rare Spellbook Star Hall X SPELL Continuous Each time a "Spellbook" Spell Card is activated, place 1 Spell Counter on this card

That of course means that it could be anything from 0.00001% of boosters up to 0.9% of booster packs containing the card, but either way its incredibly rare and very desirable

You may notice I am not particularly fond of flippy cards and sometimes leave them out while on the other hand I am quite fond of disruption cards

These days its rare to see painful draw spells that cost less than three mana, but in formats where Sign in Blood and Nights Whisper are legal, they stand the test of time