This feature allows users to customize the compartment sizes to fit various card-related items, making it versatile for different decks
Then you can tap him for no mana to prevent all combat damage a dork would deal this turn, and the controller and the attacked one draw half damage in cards
There are a couple of green Planeswalkers that have card draw abilities on them, but the best one, in my opinion is Garruk, Primal Hunter
The doubled damage isn't dealt by Lightning unless it was the original source of damage
This one focuses on using it for value and a mana advantage, but you could lean much harder into the combo side of things and use its discount alongside cards like Bolas's Citadel and Aetherflux Reservoir to generate mana for a proper storm deck
If you ran an untap landfall, you can untap them and keep it up