Any enters-the-battlefield abilities of the copied creature will trigger when Copycrook enters the battlefield
// In the card advantage department, Bred for the Hunt, Path of Discovery (also create counters), Shapers of Nature (also create counters), Zameck Guildmage and Etched Oracle are repeatable draw while Rishkar's Expertise, Prime Speaker Zegana, Painful Truths and the aforementioned Abzan Charm are 1-shot card draw
For example, since Mangara only has 2 power it can be a strong utility creature to cheat out in Alesha, Who Smiles At Death
While you could definitely build more around these lifegain and life drain mechanics, Ive recently built several decks like that so I leaned more into the auras
You essentially try your chance to get the one card you need, and sometimes you end up with totally useless junk
18 Lands So if 16 lands is the energetic little brother of 17 lands, I guess that makes 18 lands the stoic, always reliable eldest of the trio