A professional printer must maintain exact color accuracy because collectors can quickly notice differences between cards
Its not the most intuitive thing ever, but any time a creature has both a -1/-1 and a +1/+1 counter on it, they both disappear
One Piece TCG: Awakening of the New Era Booster Display (24) (OP-05)
While some of these references are pretty well known, others require a bit of digging into the card games thousands of entries
Curse Necrofear x1 Curse is a more powerful version of Dark Necrofear: it doesn't have the "Must first be special summoned" clause anymore, cycles the banished fiends for the summon for its counterpart and their effect synergizes more with Loading
The upside is that when someone wipes the battlefield, Genestealer Patriarch will give us a quick recovery, seeing all the creatures with infection counters die