TL:DR: I like Harpies, these are the cards I came up with, that can remedy their consistency problems (too few searches that are too slow and lack of quick and reliable special summons and extra deck monsters providing more utility and monsters to end on) 1
Should you check it out
Dark Tuner Catastrogue Level 8 DARK Fiend / Tuner / Effect You can only use the [1] effect of this card once per turn
Creature - Knight Zombie Color tag templates(None) Ministrant of Obligation Afterlife 2 (When this creature dies, create two 1/1 white and black Spirit creature tokens with flying.) Creature - Human Cleric Color tag templates(None) Murderous Rider Lifelink When this creature dies, put it on the bottom of its owner's library
But it has its uses, specifically alongside cards like Jhoira, Weatherlight Captain that generate oodles of card advantage so long as theres plenty of 0-cost artifacts to go around
Less rare than the Blue Back, but the holographic Prisms from this print run remain highly coveted