Vivien, Arkbow Ranger, as powerful as it is, was a planeswalker that was printed at the wrong time
Do some mana fixing by copying Urborg, Tomb of Yawgmoth or commander protection by copying Karakas as long as either of them are in a graveyard
Based on your selections that means drawing 4 or more lands in the first 5 turns
The first shows a pretty average pack while the second shows the best-case scenario Play Booster
Brawl Not Legal Vintage Legal Timeless Not Legal Commander Legal Pauper Not Legal Oathbreaker Legal Penny Not Legal Toolbox Notes and Rules Information for Callidus Assassin: Callidus Assassin copies exactly what was printed on the original creature (unless that creature is copying something else or is a token
Honestly, after seeing so many of them on this list, it was quite a relief that there isnt a Pikachu in the number one spot