Yes, Goblin Grenade was a very competitive card in the format where Force of Will is a staple
It was heavily synergetic as a pro-artifact set that included cards like Bosh, Iron Golem, Commander's Sphere, and Spine of Ish Sah that were perfect here
As you can see, Modern Horizons 3 looks like a powerful set that has the potential to really shake up Commander at all power levels
while all colors but white have at least one extra turn spell, the majority of these effects and most of the best ones are from blue cards
Gate decks are real in this format, and this is a pretty powerful payoff, as getting in with this just nets you so much value
There are 108 multicoloured Planeswalkers: 12 Azorius (white/blue) 12 Golgari (black/green) 12 Gruul (red/green) Ten Izzet (blue/red) Nine Dimir (blue/black) Nine Orzhov (black/white) Nine Simic (green/blue) Eight Boros (red/white) Seven Rakdos (black/red) Seven Selesnya (green/white) Six Grixis (blue/black/red) Two Bant (green/white/blue) Two Esper (white/blue/black) One Jund (black/red/green) One Temur (green/blue/red) One Jeskai (blue/red/white) Of course, some characters have more Planeswalker cards than others