Chain Mechanics?

Anyone figure out how chain works yet?

Can sub projectiles like lightning arrow has chain to the same target initially? How about after chaining to other targets first?

Can an enemy be hit more than once via one projectile if it chains to X enemies in between chains? What is X?

Can a subprojectile chain to an enemy hit by the initial main projectile after first chaining to something else?

Can subprojectiles eventually chain to the same enemy?

How does extra primary projectiles affect chaining with multi hits between primary and sub projectiles?

Do projectiles favor monsters over other things like lightning arrow, vice versa, or neither?