Servants are primarily obtained via summoning. 3★ Servants or below may be summoned for 200 Friend Points each, and 3-5★ servants for 3 Saint Quartz each. Some Servants can be obtained as special rewards during events.
You can Ascend Servants to increase their maximum level, slightly changing their art and battle sprites. Ascending can also unlock new skills, all of which can be reinforced. Their Noble Phantasms can also be upgraded; combining the same Servant upgrades the NP level, while completing Interludes may upgrade the rank.
Craft Essences can be equipped to your servants to increase their stats and abilities.
Feeding Servants Experience Cards or other Servants grants experience. When enough experience is gained to level up, their ATK and HP increases. Status Up Cards also increase ATK and HP, but these stat gains are independent of levels and have a maximum value of 1000 per Servant. It is now possible to have Servants gain yet another 1000 points to each stat with the inclusion of 4★ Status Up Cards.
Each Servant has an Attribute that also slightly affects their performance in battle.
Servants can also be found as enemies in quests.
When starting a quest, you can choose another player's Support Servant based on each class to help you in battle.
There are currently 233 Servants, of which 86 are limited or unplayable (As of December 2018), either because they were only obtainable as event rewards, they have not been added to the general summoning pool yet, or they are only available for limited times.
- Beast I (Goetia) is like Demon Pillar's ?-class
- Beast II (Tiamat) and Corrupted Ushiwakamaru's ?-class are like Shielder-class
- Beast III/R (Heaven's Hole) is like Broken Class
- In the story, some Servants are not part of the Grail War, thus don't disappear when the war is over. This mainly applies to characters who exist in that era (Jeanne for Orléans, Nero [Was not a Servant in the Septem Singularity] for Septem and Drake for Okeanos).
- Fate/Grand Order Exclusive Servant