Scouting

Summoning a character involves one of the following: spend Dragon Vein stones or Edgar Tickets to pull on Pick Up Banners, use farmable Flyers, or get them as stage rewards. Other items such as specific rarity tickets and referrals are also options if you happen to spend on the game.

Free Characters

You get these for free as a one-time reward once you beat a particular stage/map:

(stage): Amorey, Barboros

(stage): Mage Goblin, Goblin Archer, Goblin Fighter

(stage): Elaine

(stage): Leonhart, Robin

Recruitment Flyers

All story and event missions have a random chance to drop a Blank, Green, Blue, or Purple recruitment flyer, sometimes they won't drop a flyer at all. Exploration missions do not drop flyers

10 Blank Flyers recruit 1 unit.
1 Green Flyer recruits 1 units
1 Blue Flyer recruits 2 units
1 Purple Flyer recruits 3 units

Flyers can recruit any unit from 1 to 6 star rarity. However, it is currently believed the flyer pool only contains units that were available at launch (Amberdon banner). It is unknown if Habbit will update the flyer pool in the future. Additionally the odds of pulling a 6 star from flyers is extraordinarily low, but it's possible!

The drop rate for flyers is currently unknown, it's assumed the rarity of a flyer drop increases with the number of units it recruits.
The rarity of the flyer does not effect the rarity of the units recruited.
Upon inquiry regarding flyer recruit rates and changes to the pool Habbit has responded "rates for the Recruitment Flyers units are considered undisclosed specification. Therefore, we are unable to provide detailed information regarding your inquiry."

Banner Rates

There is no pity system. And there is not benefit in doing 10 pulls. All new units are added into the latest gacha banner, and no units are limited.