Seclusion

Protection from everything.
When Solitude enters, choose one:
•Exile all other creatures
•Tap all other creatures
Only one creature may attack per turn
Only one creature may block per turn
{w}{t}:Tap all creatures. Then untap one of them.

Solitude vivifies; seclusion kills. The worst cruelty that can be inflicted on any being is seclusion. It is a poison that decays, deforms and ultimately destroys the inner self.