You may have Estrid's Invocation enter as a copy of an enchantment you control, except it has "At the beginning of your upkeep, you may exile this enchantment. If you do, return it to the battlefield under its owner's control."

Manifest the top card of your library, then put two +1/+1 counters on it. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

Enchant creature

Enchanted creature has "Whenever this creature attacks, create a 4/4 white Angel creature token with flying that's tapped and attacking. Exile that token at end of combat."

Each creature you control gets +3/+3 until end of turn and must be blocked this turn if able.

, Discard a card with mana value X: Knollspine Invocation deals X damage to any target.

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.)

Destroy all creatures. If the gift was promised, return a creature card put into your graveyard this way to the battlefield under your control.

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Enchant creature

Enchanted creature has double strike.

If Twinblade Invocation would be put into a graveyard from anywhere, exile it instead.