Setessan Training — ruling 1

If the creature Setessan Training would enchant is an illegal target by the time the Aura spell resolves, the entire spell doesn't resolve. It won't enter the battlefield, so its ability won't trigger.

Setessan Training : règles, fonctionnement et interactions (MTG)

Setessan Training 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 you control When this Aura enters, draw a card. Enchanted creature gets +1/+0 and has trample. (It can deal excess combat damage to the player or planeswalker it's attacking.)

How it works : Setessan Training

Original English text — Wizards of the Coast / Scryfall

#1June 23, 2020· Wizards of the Coast
If the creature Setessan Training would enchant is an illegal target by the time the Aura spell resolves, the entire spell doesn't resolve. It won't enter the battlefield, so its ability won't trigger.
No other card is named in this ruling.