There are more than a few ways to get Sekki on the battlefield under normal circumstances. You could, for example, sacrifice eight Spirits. Or you could get Sekki into your library and activate Lifespinner’s ability. That’s not even counting possible ways to cheat him into play from your hand (Elvish Piper) or graveyard (Zombify), even though those options aren’t presented in this puzzle.

That said, there’s a far more conventional way to get Sekki back under your side of the field, and it involves simply casting him from your hand.

1. Sacrifice Carven Caryatid to Phyrexian Altar to add to your mana pool.
2. Sacrifice Forked-Branch Garami to Phyrexian Altar to add to your mana pool.
3. Forked-Branch Garami’s two Soulshift abilities trigger. Use these to return Elvish Spirit Guide and either Lifespinner, Verdant Eidolon, or Shinen of Fury’s Fire from your graveyard to your hand.
4. Exile Elvish Spirit Guide from your hand to add to your mana pool.
5. Pay 2 life to cast Noxious Revival on Sekki, Seasons’ Guide. Put Sekki on top of your library. You are now at 14 life.
6. Tap one mountain to add , and tap four forests to add (all used as generic mana) to your mana pool.
7. Spend to cast Manamorphosis, adding (both used as generic mana) to your mana pool. Draw Sekki, Seasons’ Guide.
8. Spend to cast Sekki, Seasons’ Guide.