Captain America, Team Leader is appropriately red, white, and blue and gives other Heroes you control vigilance and haste until the end of turn when they enter play along with a +1/+1 counter, with Cap also getting a +1/+1 counter of his own
Ive got your answers right here
Paying four life seems a bit high for a single card, but the Library allowed you to effectively see into your future by a full two turns
Stuck hasnt been bad by any means, and it can answer a lot of strong rares that depend on attacking (i.e., Lightning, Army of One)
With my Seraph Sanctuary and Bishop of Wings in play, giving me a boost of 50 life, my opponents had to have an exile or bounce wrath or face death if I untapped with my army
The card draw with Kumena's Awakening and Secrets of the Golden City are decent