Tentative Connection — ruling 1

To determine the total cost of a spell, start with the mana cost or alternative cost you're paying, add any cost increases, then apply any cost reductions (such as that of Tentative Connection). The mana value of the spell remains unchanged, no matter what the total cost to cast it was.

Tentative Connection — ruling 2

Once you announce that you're casting Tentative Connection, no player may take actions until the spell has been paid for. Notably, opponents can't try to change whether you control a creature with menace.

Tentative Connection — ruling 3

Tentative Connection is unaffected if you no longer control a creature with menace after you've cast it. You won't have to pay an additional {3}.

Tentative Connection — ruling 4

Tentative Connection can target any creature, even one that you already control or that is already untapped.

Tentative Connection : règles, fonctionnement et interactions (MTG)

Tentative Connection 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 costs less to cast if you control a creature with menace. Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn.

How it works : Tentative Connection

Original English text — Wizards of the Coast / Scryfall

#1April 17, 2020· Wizards of the Coast
To determine the total cost of a spell, start with the mana cost or alternative cost you're paying, add any cost increases, then apply any cost reductions (such as that of Tentative Connection). The mana value of the spell remains unchanged, no matter what the total cost to cast it was.
No other card is named in this ruling.
#2April 17, 2020· Wizards of the Coast
Once you announce that you're casting Tentative Connection, no player may take actions until the spell has been paid for. Notably, opponents can't try to change whether you control a creature with menace.
No other card is named in this ruling.
#3April 17, 2020· Wizards of the Coast
Tentative Connection is unaffected if you no longer control a creature with menace after you've cast it. You won't have to pay an additional .
No other card is named in this ruling.
#4April 17, 2020· Wizards of the Coast
Tentative Connection can target any creature, even one that you already control or that is already untapped.
No other card is named in this ruling.