More of That Strange Oil...

To proliferate means to choose any number of permanents and/or players that have a counter, then give each one additional counter of each kind that permanent or player already has.

In a Two-Headed Giant game, poison counters are shared by the team. If more than one player on a team is chosen this way, only one of those players can be given an additional poison counter. The player who proliferates chooses which player that is. See rule 810, “Two-Headed Giant Variant.”

To “scry N” means to look at the top N cards of your library, then put any number of them on the bottom of your library in any order and the rest on top of your library in any order.

If a player is instructed to scry 0, no scry event occurs. Abilities that trigger whenever a player scries won’t trigger.

If multiple players scry at once, each of those players looks at the top cards of their library at the same time. Those players decide in APNAP order (see rule 101.4) where to put those cards, then those cards move at the same time.

An ability that triggers whenever a player scries triggers after the process described in rule 701.18a is complete, even if some or all of those actions were impossible.