Titanoth Rex — ruling 1

Some cards with cycling have an ability that triggers when you cycle them, and some cards have an ability that triggers whenever you cycle any card. These triggered abilities resolve before you draw from the cycling ability.

Titanoth Rex — ruling 2

Triggered abilities from cycling a card and the cycling ability itself aren't spells. Effects that interact with spells (such as that of Cancel) won't affect them.

Titanoth Rex — ruling 3

You can cycle a card even if it has a triggered ability from cycling that won't have a legal target. This is because the cycling ability and the triggered ability are separate. This also means that if either ability is countered (with Disallow, for example), the other ability will still resolve.

Titanoth Rex : règles, fonctionnement et interactions (MTG)

Titanoth Rex 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

Trample Cycling (, Discard this card: Draw a card.) When you cycle this card, put a trample counter on target creature you control.

How it works : Titanoth Rex

Original English text — Wizards of the Coast / Scryfall

#1April 17, 2020· Wizards of the Coast
Some cards with cycling have an ability that triggers when you cycle them, and some cards have an ability that triggers whenever you cycle any card. These triggered abilities resolve before you draw from the cycling ability.
No other card is named in this ruling.
#2April 17, 2020· Wizards of the Coast
Triggered abilities from cycling a card and the cycling ability itself aren't spells. Effects that interact with spells (such as that of Cancel) won't affect them.
No other card is named in this ruling.
#3April 17, 2020· Wizards of the Coast
You can cycle a card even if it has a triggered ability from cycling that won't have a legal target. This is because the cycling ability and the triggered ability are separate. This also means that if either ability is countered (with Disallow, for example), the other ability will still resolve.
No other card is named in this ruling.