If your big bad monsters are constantly getting exiled or killed and you aren't adjusting your deck to run more protection, you've only got yourself to blame
You choose which nonland permanent Clever Impersonator will copy, if any, as it enters the battlefield
Starting Town Starting Town is a 5c land that has similarities with lands like Mana Confluence or City of Brass
Tombstalker A 5/5 flier for 8 mana was probably good in MTGs early days, but Tombstalker becomes interesting when you can reduce the mana cost by a lot
Gix, Yawgmoth Praetor $17 Super overpriced right now, but has good applications in an aggressive deck, as this effect snowballs quickly
When you play it, it can exile the largest threat on the board, but if something stronger comes out, you may be able to get an attack in and abduct something else