If you just want a serialized card to say you own one, however, and you arent particular about which one you own I say wait
Collective Brutality Another card that is so good you are more than happy playing it with no graveyard synergies at all
You can use rituals, such as Mana Geyser, Seething Song, Pyretic Ritual, and Desperate Ritual

1 Thoughtseize 2 Prismatic Vista 4 Ignoble Hierarch 4 Yawgmoth, Thran Physician 4 Marionette Apprentice 2 Forest 1 Swamp 1 A-Blood Artist 1 Echoing Cavern 4 Badgermole Cub 4 Birthing Ritual 2 Delighted Halfling 1 Nurturing Peatland 1 Birds of Paradise 3 Blooming Marsh 1 A-Haywire Mite 1 Wastewood Verge 4 Overgrown Tomb 1 Yavimaya, Cradle of Growth 1 Urborg, Tomb of Yawgmoth 4 Young Wolf 1 Hapatra, Vizier of Poisons 1 Boggart Trawler 1 Sephiroth, Fabled SOLDIER 1 Chittering Illuminator 2 Boseiju, Who Endures 4 Chord of Calling 1 Phyrexian Tower 1 Endurance 1 Khalni Garden 1 Kraul Harpooner 1 Endurance 1 Skyfisher Spider 1 Surgical Extraction 1 Reclamation Sage 1 Chittering Illuminator 2 Necromentia 1 Pile On 2 Abrupt Decay 1 Force of Vigor 1 Opposition Agent 2 Thoughtseize Timeless Written by Dave Finseth No changes With no archetype making up more than four percent of the metagame, Timeless is in great shape

To top it off, you also get to pair K-9 up with any of the legendary Doctor cards as well
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