Hedron Rover

Artifact Creature — Construct

Produces: nothing.

Cares about: a land entering the battlefield.

Partners

320 cards can cause a Robot or Construct it boosts.

1. Ultron, Machine Overlord — Ultron, Machine Overlord gives Hedron Rover bigger stats

406 cards can cause a land entering the battlefield.

1. Gerrard's Hourglass Pendant — When Gerrard's Hourglass Pendant enters, Hedron Rover gives +2/+2
2. Burnished Hart — When a land enters thanks to Burnished Hart, Hedron Rover gives +2/+2
3. Staff of Titania — When a Forest enters thanks to Staff of Titania, Hedron Rover gives +2/+2
4. Endless Sands — When Endless Sands enters, Hedron Rover gives +2/+2
5. Northampton Farm — When Northampton Farm enters, Hedron Rover gives +2/+2
6. Wayfarer's Bauble — When a land enters thanks to Wayfarer's Bauble, Hedron Rover gives +2/+2
7. Scaretiller — When a land enters thanks to Scaretiller, Hedron Rover gives +2/+2
8. Horizon of Progress — When Horizon of Progress enters, Hedron Rover gives +2/+2

58 other cards cause it too, equally specific. The ones shown are the best connected.