Most played cards in Robots:

4 Decks
Goblin Welder
16 copies - 4 average
Wasteland
16 copies - 4 average
Tangle Wire
16 copies - 4 average
Mishra's Workshop
16 copies - 4 average
Tormod's Crypt
15 copies - 3.75 average
Pyrostatic Pillar
15 copies - 3.75 average
Sphere of Resistance
15 copies - 3.75 average
Blood Moon
15 copies - 3.75 average
Juggernaut
12 copies - 3 average
Volcanic Island
12 copies - 3 average
Su-Chi
12 copies - 3 average
Shivan Reef
12 copies - 3 average
Rack and Ruin
10 copies - 2.5 average
Red Elemental Blast
10 copies - 2.5 average
Karn, Silver Golem
6 copies - 1.5 average
Overload
6 copies - 1.5 average
Triskelion
5 copies - 1.25 average
Lava Dart
4 copies - 1 average
Tolarian Academy
4 copies - 1 average
Black Lotus
4 copies - 1 average