Warcries are the other new sort of skill and serve as effects that share a cooldown and scale based on how many monsters are nearby when the skill is triggered. And there are more skills beside that; those are just the two new types of skills. Check out the full skills page for all sorts of new tricks to disassemble your opponents with extreme prejudice.
[Source: Official skill reveal page]
Path of Exile‘s next major update, The Awakening, is introducing not one, not three, but two new types of skills to the game. There are more than a dozen new gems for players to use on the monsters of the game, and among those new skills are Golems and Warcries. The former allows players to summon specialized minions that are more durable than normal minions, with the sole restriction being that players may have only a single Golem out at once; re-summoning replaces that Golem.