mekk knight deck yugioh Mystery may be 1st or Unlimited Edition Mekk-Knight - Yugipedia

This alone gives you countless options, as you have a free search for every Tuner in your deck

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GHALTA AND MAVREN After being summoned by the Sun Empire to ambush the Phyrexians invading Ixalan, the elder dinosaur Ghalta cut loose among the remaining Phyrexian ranks

As an additional cost to cast this spell, you may exile any number of black cards from your hand

If you can tap a creature for more than three mana, Sword Of The Paruns attached to it will always generate infinite mana at instant speed as you can keep untapping and tapping it for mana to use for Sword Of The Paruns' untap effect

Zoanthrope is probably the biggest potential monster, offering both card draw and direct damage on top of a flying creature that's slightly more difficult to kill than either Niv-Mizzet