In order to summon heroes in Fire Emblem: Heroes, you need to gather as many orbs as you can. They are not that easy to come by but you can farm them via the tips we provide through this Fire Emblem Heroes Orb Farming Guide.
Fire Emblem Heroes Orbs are in currency and each has a different color. Each color is used to summon a different hero which is the main reason these are so rare. The drop rate is low so it is best not only farm this but use this wisely.
You can get orbs via the Story maps but also remember to log-in at least once a day to get extra orbs. Also, focus on completing quests to get more orbs.
Fire Emblem Heroes Orb Farming Guide
Fire Emblem Heroes orb farming is not very difficult to do but it takes time and commitment. Logging in daily to reap the reward is the best way to farm in any mobile game. Log in every day to get more orbs and also keep an eye on special quests of the day. These quests will be random but give you an opportunity to get even more orbs to summon heroes.
Every special quest may not drop these orbs but keep an eye out for the ones that do and do not miss them. Like I mentioned above, Fire Emblem: Heroes Orb farming takes commitment and time. Keep in mind that hero ranking may increase with time and the more you pay to the gacha.
There is a lot of grinding here but keep in mind that you can always buy in-game currency.