Literally anything that adds two creatures or three or more power is lethal
This is strictly better than nearly every other board wipe, and its going to be absolutely everywhere
You can't attack with them the same turn you play them, unless they have haste
Splashability: 4 Not only is Thoughtseize quite splashable, it is frequently splashedalong with Push as a deck's interactive backbone, or as part of a sideboard strategy to provide insulation against synergy-dependent decks
To keep the fun of Set Boosters, we needed some variance in the slots, so we couldn't lock down exactly how many of each rarity a particular booster would have, but we needed to up the number of commons
And that, my friends, has made all the difference