Hide // Seek
Both halves answer their question by relocation, not destruction, and that is the through-line that makes this split worth one card slot. Hide does not kill an artifact or enchantment: it tucks the permanent to the bottom of its owner's library, which sidesteps indestructibility and strands any death-trigger or graveyard recursion the deck wanted to lean on. The card is simply gone, buried under a full deck, with no body to bring it back. Seek is the rarer effect, a surgical reach into an opponent's library to exile one chosen card before it ever appears; you gain life equal to its mana value as a footnote. The lifegain is incidental, a small reward for the trouble; the targeting clause is the whole point. This is denial of a specific piece, the singular combo component or the one threat a deck cannot operate without, taken from the zone where it is most vulnerable: out of sight, before it is drawn. The two halves cover opposite corners of the same problem, which is what split cards built around flexibility do. One color pair handles a stuck permanent; the other handles a hidden engine. Neither is a broad answer, and the design assumes you will want exactly one of them in a given game, never both at once. That is the trade an asymmetric split makes explicit: two narrow tools welded into a single draw, each precise where ordinary removal is blunt.
