Quelle & MTG SStarting with Time Spiral, there has been a change in how premium cards are distributed. Previously, premium cards replaced a card of the same rarity, so a premium rare would replace a standard rare, a premium uncommon would replace a standard uncommon, and a premium common would replace a standard common. In Time Spiral and in future sets, all rare, uncommon, and common premium cards will replace a standard common instead. It is now possible for there to be two rares in one pack, the standard rare card plus a premium rare (which replaces a standard common).
Eigentlich dachte ich, dass das nur die Bonuskarten von TS betrifft, aber eigentlich gilt das für Rares oO Forensuche brachte kein Ergebnis, also schätze ich, dass das neu ist!