Those cards are: Essence of Orthodoxy, Seedpod Caretaker, Phyrexian Pegasus, Interdisciplinary Mascot, Referee Squad, Zephyr Winder, Terror of Towashi, Seer of Stolen Sight, Injector Crocodile, Orthion, Hero of Lavabrink, Axgard Artisan, Cragsmasher Yeti, Surrak and Goreclaw, Ruins Recluse, and Fairgrounds Trumpeter.
add 1 "Ojama" card from your Deck to your hand, then send 1 Ojama card from your Deck to the GY
A different example of this would be that I rate Lightning Helix as a very powerful card but only as a fairly average burn spell
When this attacking card destroys an opponent's monster by battle: You can target 1 FIRE monster in your GY
The classic cards to dish out with a Harmless Offering are cards that are bad to control
Post-board you should replace them with Extirpate