Lust for War — ruling 1

Lust for War's triggered ability triggers when the enchanted creature becomes tapped for any reason, not just when it attacks.

Lust for War — ruling 2

If, during its controller's declare attackers step, the enchanted creature is tapped, is affected by a spell or ability that says it can't attack, or is affected by "summoning sickness," then that creature doesn't attack. If there's a cost associated with having that creature attack, its controller isn't forced to pay that cost, so the creature doesn't have to attack in that case either.

Lust for War : règles, fonctionnement et interactions (MTG)

Lust for War 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

Enchant creature Whenever enchanted creature becomes tapped, this Aura deals 3 damage to that creature's controller. Enchanted creature attacks each combat if able.

How it works : Lust for War

Original English text — Wizards of the Coast / Scryfall

#1June 15, 2010· Wizards of the Coast
Lust for War's triggered ability triggers when the enchanted creature becomes tapped for any reason, not just when it attacks.
No other card is named in this ruling.
#2June 15, 2010· Wizards of the Coast
If, during its controller's declare attackers step, the enchanted creature is tapped, is affected by a spell or ability that says it can't attack, or is affected by "summoning sickness," then that creature doesn't attack. If there's a cost associated with having that creature attack, its controller isn't forced to pay that cost, so the creature doesn't have to attack in that case either.
No other card is named in this ruling.