Grandmother Goby

Four mana and a severe self-imposed restriction are far behind Modern's pace; even spell-heavy decks generally need their spells to resolve.

Could be wrong if Ruby Storm or another cheap cast-trigger shell could exploit countered originals while retaining meaningful payoffs.

Legacy's efficient engines make a four-mana 2/2 poor setup, and mandatory self-countering is a major cost without a demonstrated exploit.

Could be wrong if Fast mana plus a cast-trigger or uncounterable-spell package could create a niche engine.

It can convert expensive spells into a board, but optimized decks rarely want a fragile four-mana creature to counter all their own noncreatures.

Could be wrong if A dense cast-trigger or uncounterable-spell package could make it a more effective token engine than expected.

The floor is a 4-mana 2/2, while converting removal and tricks into vanilla tokens is usually a losing exchange without strong token synergies.

Could be wrong if Unknown token payoffs, spell quality, and removal density could substantially improve or worsen its conversion effect.