Sometimes cards have two (or even four) modes and none of them are good enough alone, but the card is better for being flexible
(Subtypes include but are absolutely not limited to: Plains, Equipment, Aura, Arcane, Jace, Curse, Urza's, Ulamog's, etc.) The ability that defines Subgoyf's power and toughness applies in all zones, not just the battlefield
Successfully killing the Invisible Stalker will take the Unflinching Courage with it
Thickness (microns): Ultra Pro PRO-Fit (50), KMC Hyper Phoenix (130) 100 Double Sleeved Card Thickness (mm): Theoretical (66), Practical (71) Water Test: Pass Deck Box Fit (mm storage): Fit: 100 good
Its good stuff
Then you can also drop it on Ancient Copper Dragon for making all of that 1d20 Treasure or trigging the equipment