Urza's Ruinous Blast

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.)
Exile all nonland permanents that aren't legendary.

Sisay, Weatherlight Captain

Sisay, Weatherlight Captain gets +1/+1 for each color among other legendary permanents you control.
{W}{U}{B}{R}{G}: Search your library for a legendary permanent card with mana value less than Sisay's power, put that card onto the battlefield, then shuffle.

Raff Capashen, Ship's Mage

Flash
Flying
You may cast historic spells as though they had flash. (Artifacts, legendaries, and Sagas are historic.)

Arvad the Cursed

Deathtouch, lifelink
Other legendary creatures you control get +2/+2.

Primevals' Glorious Rebirth

(You may cast a legendary sorcery only if you control a legendary creature or planeswalker.)
Return all legendary permanent cards from your graveyard to the battlefield.

Jhoira, Weatherlight Captain

Whenever you cast a historic spell, draw a card. (Artifacts, legendaries, and Sagas are historic.)

Jodah, Archmage Eternal

Flying
You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.