Geist-Fueled Scarecrow — ruling 1

Geist-Fueled Scarecrow’s ability applies to creature spells even if you’re casting them for an alternative cost (such as that of emerge). If you cast a creature spell without paying its mana cost, you’ll still have to pay {1}.

Geist-Fueled Scarecrow — ruling 2

Abilities that reduce the cost of a spell apply after abilities that raise them. For example, Bedlam Reveler will cost {R}{R} to cast if you have seven instant and sorcery cards in your graveyard while you control Geist-Fueled Scarecrow.

Geist-Fueled Scarecrow : règles, fonctionnement et interactions (MTG)

Geist-Fueled Scarecrow is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Creature spells you cast cost more to cast.

How it works : Geist-Fueled Scarecrow

Original English text — Wizards of the Coast / Scryfall

#1July 13, 2016· Wizards of the Coast
Geist-Fueled Scarecrow’s ability applies to creature spells even if you’re casting them for an alternative cost (such as that of emerge). If you cast a creature spell without paying its mana cost, you’ll still have to pay .
No other card is named in this ruling.
#2July 13, 2016· Wizards of the Coast
Abilities that reduce the cost of a spell apply after abilities that raise them. For example, Bedlam Reveler will cost to cast if you have seven instant and sorcery cards in your graveyard while you control Geist-Fueled Scarecrow.
No other card is named in this ruling.