Heather, Between Two Worlds

Companion Bound {I}(You may have two commanders if both have Companion Bound.){/I} Trust When Heather, Between Two Worlds, enters the battlefield, choose Dragons or Humans. {I}.Dragons--{/I}Dragons you control get +1/+1 and Double-Strike. {I}.Humans--{/I}Humans you control gain +1/+1 and Lifelink.