Rampaging War Mammoth
Creature — Elephant
Trample
Cycling 
(, Discard this card: Draw a card.)
When you cycle this card, destroy up to X target artifacts.
The Mûmakil of Harad were great beasts, like moving houses, capable of dragging huge towers and engines to war.
Simon Dominic
Rulings
You can choose 0 as the value of X in Rampaging War Mammoth's cycling cost. In that case, its triggered ability won't have any targets and won't destroy any artifacts.
(wotc • 2023-06-16)
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, the other ability will still resolve.
(wotc • 2023-06-16)
Triggered abilities from cycling a card and the cycling ability itself aren't spells. Effects that interact with spells (such as Saruman's Trickery) won't affect them.
(wotc • 2023-06-16)
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.
(wotc • 2023-06-16)
Rulings
You can choose 0 as the value of X in Rampaging War Mammoth's cycling cost. In that case, its triggered ability won't have any targets and won't destroy any artifacts.
(wotc • 2023-06-16)
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, the other ability will still resolve.
(wotc • 2023-06-16)
Triggered abilities from cycling a card and the cycling ability itself aren't spells. Effects that interact with spells (such as Saruman's Trickery) won't affect them.
(wotc • 2023-06-16)
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.
(wotc • 2023-06-16)