You could attack someone you know will kill it, but often you are looking to attack the player you stole it from, and they may prefer to not kill it, hoping they'll get it back on their turn
Returning mechanics center around Historic, Disguise, and Cloak which all seem incredibly fitting for assassins

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Its good in angel decks, blink decks, and ramp decks, as well as in reanimator decks thanks to cycling
It has a solid enough foundation that can be built on with some staples like Second Harvest and Avenger of Zendikar