Giddy Goop
Tier 2 Finale Goo
Giddy Goop is a Tier 2 trinket in Grounded. Its effect is Finale Goo. In-game it is described as: "Mysteriously excited firefly goo ready to jump out at your foes."
A trinket occupies a utility slot — it grants a passive effect rather than raw armor or damage, so it competes with your damage and survival perks for that slot.
The effect it grants is Finale Goo, which is what you are really equipping it for; the slot is better spent here than on a trinket whose effect you will not trigger.
You get it via Firefly.
Verdict: Overall Giddy Goop is a Tier 2 trinket best used when its Finale Goo effect fits the fight ahead.
Finale Goo
Trinket effect
How to get: Firefly
Mysteriously excited firefly goo ready to jump out at your foes.
