Margulis
The Archimedean who protected the Zariman children, developed the Transference treatment and defied Orokin judgement.
What the treatment was for
The dream and Transference were first developed not to manufacture child soldiers but to calm uncontrolled Void power. That the Tenno could form a particular bond with the pain of Warframe bodies is what let Ballas turn a treatment into a combat system.
How she differed from Ballas
Margulis lived love as letting the other person keep their own identity. Ballas laid claim to the face and the memory of the person he loved. That opposition resolves in The New War, when Lotus chooses her own name.
Her relationship with Lotus
Lotus is not a resurrected Margulis. Natah first used her likeness and her model of motherhood to infiltrate; the more she chose to protect the children, the more the role became her own Lotus identity. Margulis's legacy lives less in that face than in the approach that counted the Tenno as human.