mtg card flash Price Whenever a creature enters the battlefield MTGNexus - The Flash

And we definitely want new players to be able to cast their spells

Hadanas Climb / Winged Temple of Orazca Winged Temple of Orazca is a rather messed up card that easily ends games

Rograkh, Son of Rohgahh was first released in the set Commander Legends, illustrated by Chris Seaman

Probably not ready for Modern primetime, but theres always something you want to drop on the last end step before your turn in Commander

Whenever this creature attacks, you may cast an Ally spell from among cards you own exiled with this creature

As long as you aren't running a Stax deck that is actively limiting your opponents from casting multiple spells per turn with cards like Winter Orb I think you'll get enough value out of Mangara to justify its slot