Going from ten 1/1 tokens to 20 1/1 tokens is quite strong, but remember that this doubles the number of all tokens regardless of what those tokens are (something that Crush of Wurms fans might enjoy)
Rare, rare will happen 1.6% of the time
With Universes Beyond products coming through Standard you can expect they'll come through Arena via Through the Omenpaths or not
Yes, the pure-healing-job has never had the most exuberant skillset, but they're undoubtedly the best of the healers right now
For example, if Vincent's power was 7 when it dealt combat damage to an opponent but is reduced to 6 just before its last ability resolves, it won't deal any additional damage when the last ability resolves
For example, if you control both Azusa and Exploration (an enchantment with "You may play an additional land on each of your turns"), you'll be able to play four lands during each of your turns