Angelic Aberration

Normally, a creature's base power and toughness are the power and toughness printed on the card or, for a token, the power and toughness set by the effect that created it. If another effect sets a creature's power and toughness to specific numbers or values, those become its base power and toughness. If an effect modifies a creature's power and/or toughness without setting them, that is not included when determining its base power and toughness.

Devoid doesn't affect the color identity of the card for the purposes of the Commander variant. For example, while Abstruse Appropriation is colorless because it has devoid, its color identity is still white and black, and it can't be included in a Commander deck where the commander's color identity doesn't include both white and black.

Some creatures have base power and toughness 0/0 and an ability that gives them a bonus based on some criteria. Those are not characteristic-defining abilities, and that ability doesn't change its base power and toughness.