A recent update has brought us an absolutely new feature that we have not seen in Dota yet; a new monthly subscription service designed to help players get the most out of every match they play.
Dota Plus is more or less an evolved form of Battle Pass that is well-known for Dota players from series of e-sports events called The International and the Majors where Valve prepares an additional in-game content even for normal players who usually pay a one-time fee to participate and experience more fun in extraordinary challenges and new missions during these events. The main difference is that the new upcoming Dota Plus subscription doesn't depend on a specific start and end date, so Dota team is not limited in any way and they promise to continually add features and content over time.
With all these pay-to-benefit features that Valve has added, a huge amount of concern has been brought out to Dota 2 fanbase making them think that this game is evolving into a pay-to-win game, which is the complete opposite of what Dota 2 promised and offered at the beginning. Nonetheless, at least Dota Plus subscription is pretty fairly priced at $3.99 per month and you receive a discount if you sign up for a six or twelve-month subscription.