Blurred Mongoose — ruling 1

It can be targeted while on the stack. Shroud only works while it is on the battlefield.

Blurred Mongoose — ruling 2

Counterspells can be cast that target it, but when they resolve they simply don’t counter it since it can’t be countered.

Blurred Mongoose : règles, fonctionnement et interactions (MTG)

Blurred Mongoose 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

This spell can't be countered. Shroud (This creature can't be the target of spells or abilities.)

How it works : Blurred Mongoose

Original English text — Wizards of the Coast / Scryfall

#1October 4, 2004· Wizards of the Coast
It can be targeted while on the stack. Shroud only works while it is on the battlefield.
No other card is named in this ruling.
#2October 4, 2004· Wizards of the Coast
Counterspells can be cast that target it, but when they resolve they simply don’t counter it since it can’t be countered.
No other card is named in this ruling.