Like Hearthstone, the game is fast paced. Matches take a few minutes. You control a hero and spend mana to summon minions and cast spells on to the battlefield. But Spellweaver has more tactical depth. Your minions can be placed in one of two lanes: a front lane and a support lane. Minions on the support lane can't participate in combat, unless they have the Flying keyword. Spellweaver also has a speed mechanic: minions can't attack or block creatures that are faster than them. In practice, this works like the Flying mechanic in Magic: the Gathering, but with four layers to it.
Like Magic: the Gathering, your cards are gated by certain types of colored resources. In Spellweaver, the mana you use to summon minions or cast spells itself is colorless. You instead level up your abilities in certain factions (Order, Corruption, Dominion, Rage, and Nature), and you can cast a card if it meets two criteria: having the requisite levels in one or more factions, and having the right amount of mana available. This works like the threshold system in Hex. One advantage that Spellweaver has over Hex is that using a resource to gain mana also draws a card, which helps eliminate the kind of resource flood issues that plagues Magic-like games, where you end up only pulling resources into your hand, and nothing to use them on. The game also allows you to trade in a card for a resource when you have the opposite problem of having plenty of things to do and no resources to cast them with.
Having become accustomed to the resource system in Spellweaver, which it has been very hard for me to go back to playing Magic or Hex, where mana screw and mana flood are much more commonplace.
Spellweaver is quite a fun game for any lover of CCGs like Magic: the Gathering. It has more depth (and less RNG) than Hearthstone, but is still quite streamlined and fast paced.
The only real drawback, for me, is that it lacks in gameplay modes other than one on one vs another player or the computer. Hex has a rather innovative PVE mode where you play through a single player campaign, and Hearthstone has a number of adventures where you play against various boss encounters with varying abilities. Those are quite fun, and hopefully this is a feature that Spellweaver will eventually adopt as the game is developed further.
If you'd like to try it, you can use my referral link to sign up with some free in-game gold to get a few free packs to start off with.