Eternal Dominion

Search target opponent's library for an artifact, creature, enchantment, or land card. Put that card onto the battlefield under your control. Then that player shuffles.
Epic (For the rest of the game, you can't cast spells. At the beginning of each of your upkeeps, copy this spell except for its epic ability. You may choose a new target for the copy.)

Mirror-Sigil Sergeant

Trample
At the beginning of your upkeep, if you control a blue permanent, you may create a token that's a copy of this creature.

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Undying Flames

Exile cards from the top of your library until you exile a nonland card. Undying Flames deals damage to any target equal to that card's mana value.
Epic (For the rest of the game, you can't cast spells. At the beginning of each of your upkeeps, copy this spell except for its epic ability. You may choose a new target for the copy.)

Beacon of Immortality

Double target player's life total. Shuffle Beacon of Immortality into its owner's library.

Enduring Ideal

Search your library for an enchantment card, put it onto the battlefield, then shuffle.
Epic (For the rest of the game, you can't cast spells. At the beginning of each of your upkeeps, copy this spell except for its epic ability.)

Worldfire

Exile all permanents. Exile all cards from all hands and graveyards. Each player's life total becomes 1.

Narset, Enlightened Master

First strike, hexproof
Whenever Narset attacks, exile the top four cards of your library. Until end of turn, you may cast noncreature spells from among those cards without paying their mana costs.

Clone Legion

For each creature target player controls, create a token that's a copy of that creature.

Mogg Infestation

Destroy all creatures target player controls. For each creature that died this way, that player creates two 1/1 red Goblin creature tokens.

Mirrorweave

Each other creature becomes a copy of target nonlegendary creature until end of turn.

Reverse the Sands

Redistribute any number of players' life totals. (Each of those players gets one life total back.)

Long-Term Plans

Search your library for a card, then shuffle and put that card third from the top.