Richard's wearing a cloak
Whenever a creature would die, its controller may its mana cost, if that player does, they may return it to their hand as a replacement effect
As such, theyre vulnerable to removal
This is notable on cards like Elvish Vanguard and Emperor Crocodile, but also on some powerful fatties like Phyrexian Ingester
Then at the beginning of your combat you can return, for free, a Pirate from your graveyard to the battlefield but you'll put a finality counter on it so if it would die, it gets exiled
Your creatures can also help produce mana , either by making things cost less (like Goblin Anarchomancer and Drumhunter) or by letting you play more lands every turn (like Loot, Exuberant Explorer or Silverback Elder Elder)