When comparing Dungeon World vs Icar, the Slant community recommends Dungeon World for most people. In the question“What are the best tabletop RPGs?” Dungeon World is ranked 4th while Icar is ranked 52nd. The most important reason people chose Dungeon World is:
Unlike other RPGs where the GM creates the world and the storyline single-handedly, here GMs are specifically asked to leave blanks and players encouraged to fill them in.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Encourages players and the GM to build the world collaboratively
Unlike other RPGs where the GM creates the world and the storyline single-handedly, here GMs are specifically asked to leave blanks and players encouraged to fill them in.
Pro Great advice and systems to help GMs along
Dungeon World provides GMs with great advice on how to run a good session.
Additionally, GMs can set conditions that, if fulfilled, will give a player XP. It gives the GM a way of enticing players to perform certain actions they might not otherwise have considered or wanted to perform.
Pro Encourages creating relationships between characters
Relationships between characters are established during the character creation process as well as at the end of each session via Bonds. Bonds are simple statements that explain how a character relates to another character. An example of a bond would be, "Avon proved himself a coward in the dungeons of Xax’takar. He is a dangerous liability to the party and must be watched." Multiple bonds can be established at a time. At the end of each session bonds resolved and new ones created give XP.
Pro Narrative driven fantasy RPG
Dungeon World is set in a D&D-esque world with a distinct slant towards combat and treasure gathering while emphasizing narrative over combat mechanics.
The game includes classic fantasy RPG classes such as Bard, Cleric, Druid, Fighter, Paladin, Ranger, Thief and Wizard and D&D style ability scores such as Strength, Dexterity, Constitution, Intelligence, Wisdom and Charisma.
Pro Has a self-regulating power balance system
In Dungeon World, XP is given for failures, and automatically for any rolls that are 6 or below. It provides many benefits and chief among them is the fact that it allows players to catch up to the difficulty of challenges faced. Additionally, it encourages the group to attempt harder challenges, reduces grief caused by failure and clears the GM from having to track each individual player's level.
Pro Encourages playing according to character's way of thinking and morality
XP is given at the end of the session if a character is acting according to alignment. Alignments are categorized as Good, Lawful, Neutral, Chaotic, and Evil.
Pro Does not require special dice
The game can be played with common six-sided dice.
Pro Super strategic hand to hand combat and piloting rules
Cons
Con Hard for the GM with non-collaborative players
Con Combat system can be confusing for some
Dungeon World's combat system is not divided into turns in order to make it more fluid. But it can get confusing as to what happens in what order. It is purposefully frantic, but that can turn off some. Especially people with preconceived notions of how RPGs should be played.
In the most basic form - GMs narrate the beginning of an NPC's action to which the player responds. If the player's response triggers a move, roll the dice. GM narrates the conclusion.
Con It's not entirely free
The text is CC-BY but the game as a whole (graphics etc) is not free. You can make and sell your own games based off it but you won't find the PDF download for free anywhere.