All three of these mana dorks have impacted my games, with Kami of Whispered Hopes being particularly strong in my Raggadragga, Goreguts Boss deck
Terra, Herald of Hope (Commander)by Marta Nael
Creatures dealing combat damage is one of the main ways to defeat your opponent , so playing creatures that can guarantee damage will always be more valuable than a creature that cant
In fact, Wizards ' marketing is designed to push players in this direction, from kitchen tables to FNMs and beyondthis is the pathway they have built, with an ever-increasing level of commitment and competition (of course, there's no single path in Magic , and there's absolutely nothing wrong with playing the game however you like, so don't worry if you haven't followed this path)
Exdeath, Void Warlock doesnt provide that level of immediate value, but build your deck properly and itll flip into Neo-Exdeath, Dimensions End the same turn it comes down and become a game-ending threat