Some include a physical or vocal component, like Blacker Lotus or the Gotcha! mechanic on Touch and Go, some have rules that specifically reference flavor text or artists, like Carnivorous Death-Parrot and Drawn Together, and some require interacting with people or objects outside the game (Ashnod's Coupon being my favorite)
It can also disable The One Ring, though you'll likely avoid this interaction since you run it, too
BOOSTER ACROSS TIME [BT-12] BT12-001 U Digi-Egg Lv.2 Gigimon Color Red Form In-Training Attribute - Type Lesser DP - Cost - Digivolve Cost 1 - Digivolve Cost 2 - Upper Text - Lower Text [Your Turn] Add 1000 to the maximum DP you can choose with DP-based deletion effects
Sower of Discord is a fun one, especially if you have more than two opponents to pick from giving you a chance for some fun politicking
This means while you can Link Summon Gaia Saber with any three monsters (each monster counting for 1 Link Rating), you can also Link Summon Gaia Saber using a LINK-2 monster (which has a Link Rating of 2) and one other monster (which adds to the Link Rating of 2 for a Total of Three)
But requries more tamers to make work
