For each creature card exiled with Lukka's first ability, you can cast it as long as you control any Lukka planeswalker, not just the one that exiled the card.

If a creature card in a player's library or a creature on the battlefield has in its mana cost, X is considered to be 0.

You still pay any costs for spells cast from Lukka's first ability. You may pay alternative costs, such as mutate costs.

In a Two-Headed Giant game, Lukka's last ability causes the opposing team to lose twice as much life as the power of your creatures.

The ability granted by Lukka's first ability doesn't change when you may cast the card.

Once you begin to cast an exiled card, losing control of Lukka won't affect the spell. You can finish casting it as normal.

You may cast creature cards exiled with Lukka's first ability as noncreature spells if a rule or effect allows you to do so. For example, adventurer cards from the Throne of Eldraine set may be cast as Adventures.

If you reveal your entire library without revealing a creature card with higher mana value, you put the library back in a random order and continue.