ksante says dfouble shield. if I have 2 does that double and double again

One K'Sante trigger doubles once — Shield 2 becomes Shield 4, not 8.

K'Sante, Dauntless says "When I attack or defend, double the [Shield] of a unit you control here this turn." Doubling adds +X where X is the Shield value at the moment it resolves (Rule 432.1) — it's a one-time snapshot add, not a live multiplier. So a unit with Shield 2 ends up at Shield 4, meaning +4 Might while it's a defender.

If you actually have two doublings going (e.g., two K'Sante, Dauntless both attacking), each trigger is a separate chain item that resolves one at a time. The first takes Shield 2 → 4; the second then snapshots the current Shield (4) and adds +4, so you'd land on Shield 8 for the turn. Same snapshot logic as Last Stand doubling a unit's current Might (FAQ 2568) — later doublings use the already-doubled value.