Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Mystical Tutor

Search your library for an instant or sorcery card, reveal it, then shuffle and put that card on top.

Island

Mana Severance

Search your library for any number of land cards, exile them, then shuffle.

Laboratory Maniac

If you would draw a card while your library has no cards in it, you win the game instead.

Counterspell

Muddle the Mixture

Counter target instant or sorcery spell.
Transmute {1}{U}{U} ({1}{U}{U}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Kaho, Minamo Historian

When Kaho, Minamo Historian enters the battlefield, search your library for up to three instant cards, exile them, then shuffle.
{X}, {T}: You may cast a spell with mana value X from among cards exiled with Kaho without paying its mana cost.