Oath of the Gatewatch (OGW): Set Guide
Some sets end a story. Oath of the Gatewatch ends a war - and begins something new. Released on January 22, 2016, it's the second and final set in the Battle for Zendikar block, wrapping up the Eldrazi threat on Zendikar while laying the groundwork for the next chapter of Magic's ongoing story. If Battle for Zendikar was the crisis, Oath of the Gatewatch is the reckoning.
What is Oath of the Gatewatch?
Oath of the Gatewatch is Magic: The Gathering's 69th expansion, set code OGW. It contains 187 cards and was released on January 22, 2016. As a small expansion - the second set in the Battle for Zendikar block - it follows the established pattern of a large set followed by a smaller one that deepens and completes the block's themes.
The set picks up directly where Battle for Zendikar left off: the plane of Zendikar under siege from the Eldrazi titans Ulamog and Kozilek. The resolution of that conflict drives both the story and the mechanics of the set.
Format check: OGW was legal in Standard from its release through rotation in September 2017. It is currently legal in Modern, Legacy, Vintage, Pioneer, and Pauper, depending on individual card legality.
Themes and mechanics
The defining mechanical identity of Oath of the Gatewatch is colorless mana as a resource. For the first time, the Eldrazi and their most powerful spells required a specifically colorless mana cost - represented by the symbol {C} - rather than generic mana that any color could fulfill. This was a genuinely novel idea: a sixth "color" of mana that wasn't a color at all, tied thematically to the alien, void-dwelling nature of the Eldrazi.
To support {C} costs, the set introduced new colorless-producing lands and made colorless mana a first-class citizen in deckbuilding, not just an afterthought.
The set also continued and concluded several themes from Battle for Zendikar:
- Devoid - spells that are technically colorless despite being in a color's portion of the set, representing Eldrazi influence bleeding into the world
- Surge - a new keyword granting a cost reduction if you or a teammate had already cast a spell that turn, rewarding two-player teamwork in Two-Headed Giant and fast sequencing in regular play
- Support - a new keyword that puts +1/+1 counters on other creatures, reflecting the Zendikari rallying together
- Cohort - an ability word for Allies, requiring you to tap the creature plus another Ally to activate an effect, deepening the tribal cooperation theme from Battle for Zendikar
Rules note: The {C} symbol is a genuine rules distinction. A card costing {C} cannot be paid with colored mana or with any-color-generic mana. It specifically requires mana that has no color identity. This was a meaningful change to how mana worked and required updates to the Comprehensive Rules.
The Oaths of the Gatewatch
The set's most narratively charged cycle is the Oath of Gideon, Oath of Jace, Oath of Chandra, and Oath of Nissa - four rare legendary enchantments, each representing a Planeswalker swearing to defend the Multiverse as a founding member of the Gatewatch. (A fifth oath, Oath of Liliana, came later in Eldritch Moon.)
Each Oath has an enter-the-battlefield effect and a second ability with a Planeswalker interaction. They're the thematic heart of the set: the moment the wandering, self-interested Planeswalkers of Magic's story commit to something larger than themselves.
This cycle marked the beginning of the Gatewatch as an ongoing team - a decision that shaped Magic's narrative for years afterward.
Lore and setting
Oath of the Gatewatch takes place on Zendikar, the plane of wild mana and perilous adventure that has been the stage for some of Magic's most dramatic story beats. By this point, Zendikar is under existential threat from the Eldrazi titans - vast, reality-devouring entities that were awakened in Rise of the Eldrazi (2010).
The set resolves the conflict with Ulamog and Kozilek, the two titans threatening Zendikar at this point in the story. The Planeswalkers - Gideon, Jace, Chandra, Nissa, and Liliana - come together not just to survive the battle but to formally commit to defending the Multiverse as a group: the Gatewatch.
Lore aside: The working title for this set was apparently Fall of the Eldrazi, which tells you something about the intended emotional weight of the story. "Oath of the Gatewatch" shifts the emphasis from what was lost to what was forged - a more hopeful frame for the same events.
Set legacy
Oath of the Gatewatch is remembered for a few things, not all of them comfortable.
The introduction of the {C} mana symbol was a genuine mechanical innovation - elegant and flavorful. The Oath cycle is some of the most thematically resonant enchantment design in recent Magic history.
The set also introduced cards that became deeply impactful in competitive formats, particularly in Modern and Legacy, where certain Eldrazi-based strategies proved extremely powerful in early 2016. That period is often cited as one of the more disruptive moments in Modern's history, leading to significant banlist action in April 2016.
In terms of story, this is where the Gatewatch begins - and depending on how you feel about that direction for Magic's narrative, Oath of the Gatewatch is either the exciting origin of a new chapter or the first step down a road that became complicated. Either way, it's an important set. The decisions made here echoed through every block that followed.
