After you cast Skyclave Shade from your graveyard, it's considered a new object, and the permission from its landfall ability won't apply to it again even if it returns to your graveyard later in the turn. You'll need to have another land enter the battlefield under your control after it has returned to your graveyard to cast it again.

Skyclave Shade's landfall ability triggers only if it's in your graveyard immediately after the land enters the battlefield.

You must follow the normal timing permissions and restrictions for Skyclave Shade when casting it with the permission of its landfall ability. You must pay its mana cost (or, if another effect allows, an alternative cost). You may pay its kicker cost when casting it this way.

A landfall ability doesn't trigger if a permanent already on the battlefield becomes a land.

The kicker ability doesn't let you pay a kicker cost more than once.

If a card or token enters as a copy of a permanent, the new permanent isn't kicked, even if the original was.

Whenever a land you control enters, each landfall ability of the permanents you control will trigger. You can put them   on the stack in any order. The last ability you put on the stack will be the first one to resolve (As a result, you can have those abilities resolve in the order of your choosing.).

If you put a permanent with a kicker ability onto the battlefield without casting it, you can't kick it.

To determine a spell's total cost, start with the mana cost (or an alternative cost if another card's effect allows you to pay one instead), add any cost increases (such as kicker), then apply any cost reductions. The spell's mana value remains unchanged, no matter what the total cost to cast it was.

If a spell's kicker cost was paid, the spell is "kicked."

A landfall ability triggers whenever a land you control enters for any reason. It triggers whenever you play a land, as well as whenever a spell or ability puts a land onto the battlefield under your control.

If you copy a kicked spell on the stack, the copy is also kicked. If the copied spell is a permanent spell, the token the copy of that spell becomes when it enters is also kicked.