With Red Brambleback, if you have Trinity Force and Skyfall of Aerion, does that two card combo trigger an additional time? Meaning you get 3 points for a conquer?

Yes, you score 3 points total when conquering with a unit equipped with Trinity Force and Skyfall of Areion at a battlefield with Red Brambleback.

The Components

• Red Brambleback: Your conquer effects for conquering here trigger an additional time.
• Skyfall of Areion: Makes the equipped unit's "When I hold..." effects also count as "When I conquer..." effects.
• Trinity Force: When I hold, score 1 point.

The Interaction

1. Skyfall of Areion modifies the Trinity Force ability on your unit. Because of Skyfall, Trinity Force's "When I hold, score 1 point" effect is now also a "When I conquer, score 1 point" effect.
2. When you conquer the battlefield where Red Brambleback is present, you trigger your unit's conquer effects.
3. Red Brambleback causes your conquer effects to trigger an additional time.

The Result

You score 3 points total from this interaction:

1. 1 point from the standard game action of conquering the battlefield.
2. 1 point from the first resolution of the Trinity Force conquer effect.
3. 1 point from the second resolution of the Trinity Force conquer effect (triggered by Red Brambleback).

Sequence:

• You conquer the battlefield.
• You gain 1 point from the conquer game action.
• The Trinity Force conquer effect (modified by Skyfall) triggers.
• Red Brambleback causes that conquer effect to trigger a second time.
• Both instances of the Trinity Force trigger are placed on the chain.
• The chain resolves, granting you 2 additional points.

Note: This assumes you have not already scored this battlefield this turn, as you can only score a battlefield once per turn (Rule 465). I could not fully verify this ruling against the retrieved rules.