One of the more controversial products printed in Magics history were the silver bordered cards from Unglued and Unhinged
Experiment Kraj gives you a +1/+1 counters theme thats fun to play around if you want to build a story with the cards in your 99
Phyrexian Portal -- $0.49 Phyrexian Portal is one of the most broken cards at multiplayer or casual Magic , bit the issue is two-fold
You'd think so, at least, but when I looked it up on EDHREC it only shows up in 5306 decks - a mere fraction of the potential lists that could be running it
Wurmwall Sweeper Wurmwall Sweeper helps you to fill your graveyard and filter the top of your deck, which can be pretty useful from a colorless 2-drop artifact
Both give you an extra turn for 5 mana, which means another attack, land drop, and draw step all rolled into one