Important things to consider in c221:

theyullenator:

• Atuuda is confirmed as not just being an ability to heal,
  but to transfer life force.
• The person most likely to run out of life force right when it’s most important, like killing/saving Allen: Kanda Yuu.
• Kanda will likely have a better chance of living longer in order to help Allen and Neah achieve their goals from the hidden side of the war.
• Kanda may stand by Allen’s side on the battlefield for longer.