Players can't gain life.Damage can't be prevented.All damage is dealt as though its source had wither. (A source with wither deals damage to creatures in the form of -1/-1 counters.)
Enchant creatureAs long as enchanted creature is white, it gets +1/+1 and has lifelink. (Damage dealt by the creature also causes its controller to gain that much life.)As long as enchanted creature is blue, it gets +1/+1 and can't be blocked.
If Mossbridge Troll would be destroyed, regenerate it.Tap any number of untapped creatures you control other than Mossbridge Troll with total power 10 or greater: Mossbridge Troll gets +20/+20 until end of turn.
Enchant creatureAs long as enchanted creature is green, it gets +1/+1 and has indestructible. (Damage and effects that say "destroy" don't destroy it. If its toughness is 0 or less, it's still put into its owner's graveyard.)As long as enchanted creature is white, it gets +1/+1 and has flying.
At the beginning of your upkeep, if you have no cards in hand, each opponent loses 2 life.At the beginning of each opponent's upkeep, if that player has no cards in hand, they lose 2 life.
