abilities can only be activated, if its controller has continuously controlled that permanent since the beginning of their most recent turn.Tezzeret the Seeker is an artifact toolbox with an untap engine attached. Its minus ability searches an artifact directly onto the battlefield, while its plus ability untaps up to two artifacts. That lets the same planeswalker either find a missing piece or improve the artifacts already working for you.
Mana rocks make the plus ability particularly productive. Untapping Thran Dynamo or other substantial mana producers can help pay for another spell, while utility artifacts may offer a second activation. The ability can target artifact creatures too, although untapping alone does not remove summoning sickness or grant another attack phase.
The search uses mana value X or less. Choosing zero can find a zero-mana artifact, including an artifact land, without spending loyalty. Larger targets require a greater loyalty payment. A deck with a compact package of answers and engine pieces can make this tutor more versatile than one built around only a single expensive artifact.
The ultimate turns your artifacts into base 5/5 artifact creatures until end of turn, potentially converting a developed artifact board into an attack. Artifacts that entered that turn can still have summoning sickness once animated. Equipment and other animated artifacts also bring rules considerations, so count your real attackers before committing. Tezzeret is strongest when its ordinary abilities already advance the plan; the combat finish then becomes another option rather than the only reason to include it.
