I like to think of Goblin Grenade as the tribal version of Fireblast or Shrapnel Blast
If four creatures die during one turn, Sephiroth turns into his famous One-Winged Angel form, ensuring that your opponent loses life, and you gain life whenever something dies
But while this represents a somewhat redundant effect in Amulet Titan due to already reliable access to Engineered Explosives, things get really interesting in Blast Zones other homes
You can get a lot of value out of this little 1/2 as long as you can consistently trigger Training
Still, the best spices to pick from are often you own, so having a few decent activated abilities for you to choose from your graveyard might be a good idea
Spider-mom asks each opponent to sac a nontoken creature or walker, which is a tasty upgrade over most other edicts