Do you need to control Dreaming Tree battlefield to get the draw trigger, or can you attack into that battlefield, Cleave your attacking unit, and draw a card?

Ruling: You do not need to control the Dreaming Tree battlefield to get the draw trigger. As long as you have a unit at the battlefield and select it as a target for a spell or ability for the first time in a turn, you will draw a card.

Sequence:

• Attack into the Dreaming Tree battlefield with your unit
• Target your attacking unit with Cleave (or another spell)
• If this is the first time this turn you've chosen a friendly unit there with a spell, draw 1 card

Nuances:

• The card was errataed to change "you" to "a player" to clarify that any player can trigger the effect when targeting their own units at the battlefield, regardless of who controls it
• This interaction is consistent with how other battlefields work (e.g., Trifarian War Camp providing +1 might to units there regardless of battlefield control)