Selvala, Explorer Returned and Life Gain

[16km]

Hopefully a quick question. Selvala, Explorer Returned says "Each player reveals the top card of his or her library. For each nonland card revealed this way, add G to your mana pool and you gain 1 life."

Is it, you gain 1 life for each nonland card revealed, or add G for each nonland card revealed, and you gain only 1 life regardless of what's revealed?

[Dice_Box]

It's a single effect. You gain as much life as you do mana.

If it was separate, the card would read:


Each player reveals the top card of his or her library. For each nonland card revealed this way, add Green to your mana pool. Then each player draws a card and you gain 1 life.