S:Mode$ Continuous | Affected$ Creature.Sliver | AddTrigger$ OnDmg | AddSVar$ FungusSliverCounters | Description$ All Sliver creatures have "Whenever this creature is dealt damage, put a +1/+1 counter on it." (The damage is dealt before the counter is put on.)
SVar:OnDmg:Mode$ DamageDoneOnce | ValidTarget$ Card.Self | Execute$ FungusSliverCounters | TriggerDescription$ Whenever CARDNAME is dealt damage, put a +1/+1 counter on it.
Oracle:All Sliver creatures have "Whenever this creature is dealt damage, put a +1/+1 counter on it." (The damage is dealt before the counter is put on.)