Lots of people have wondered when characters from Dota 2's animated spinoff Dota: Dragon's Blood would make their way into the game, and the answer is: Soon. Marci was announced at The International 2021 as the next hero to come to Valve's MOBA. A trailer with both 2D animation in the style of the show and a transition to Marci's 3D model was released today.
Marci's a companion to archer Mirana, something between servant and friend, and rarely says anything—never says anything aloud, at least. She's quite content to communicate with signs. While Marci at first seems like a simply kind, if insistent, friend, she later reveals some serious strength and a hidden prowess at unarmed combat. Her incredible strength is played both as a joke, and deadly seriously, in the anime.
Marci's probably not the first choice people would have guessed to get added, as teleporting elf Fymryn is both a more prominent character and more obviously suited as a moba hero. Nonetheless, Marci is a fan favorite and her inclusion is unlikely to make anyone sad.
There's no word yet on what Marci's abilities will be, but according to the trailer Marci “joins the fight this fall.”
Some players are speculating that given Marci's power, and the trailer showing her fighting a Jungle monster, she'll take the role of a hard carry in the game. If so, she'd be the first real hard carry added in quite a few years. My memory may fail me, but the last I can remember was Arc Warden in 2015.