Horror of the Broken Lands — ruling 1

Some cards have an ability that triggers whenever you cycle any card. These triggered abilities resolve before you draw from the cycling ability.

Horror of the Broken Lands — ruling 2

An ability that triggers whenever you discard a card doesn't give you permission to discard cards. You'll need another effect that instructs or allows you to discard them.

Horror of the Broken Lands — ruling 3

An ability that triggers whenever you "cycle or discard" a card triggers only once if you cycle a card. The ability "Whenever you discard a card" is functionally identical to this ability; cycling is mentioned for clarity.

Horror of the Broken Lands — ruling 4

If a player discards a card during their cleanup step due to having too many cards in hand, any appropriate abilities that trigger on discarding that card trigger. If this happens, those triggered abilities are put onto the stack and players receive priority in that cleanup step to cast spells or activate abilities (normally, no players may take actions during a cleanup step). Another cleanup step is created following that one.

Horror of the Broken Lands : règles, fonctionnement et interactions (MTG)

Horror of the Broken Lands 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

Whenever you cycle or discard another card, this creature gets +2/+1 until end of turn. Cycling (, Discard this card: Draw a card.)

How it works : Horror of the Broken Lands

Original English text — Wizards of the Coast / Scryfall

#1April 18, 2017· Wizards of the Coast
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 18, 2017· Wizards of the Coast
An ability that triggers whenever you discard a card doesn't give you permission to discard cards. You'll need another effect that instructs or allows you to discard them.
No other card is named in this ruling.
#3April 18, 2017· Wizards of the Coast
An ability that triggers whenever you "cycle or discard" a card triggers only once if you cycle a card. The ability "Whenever you discard a card" is functionally identical to this ability; cycling is mentioned for clarity.
No other card is named in this ruling.
#4April 18, 2017· Wizards of the Coast
If a player discards a card during their cleanup step due to having too many cards in hand, any appropriate abilities that trigger on discarding that card trigger. If this happens, those triggered abilities are put onto the stack and players receive priority in that cleanup step to cast spells or activate abilities (normally, no players may take actions during a cleanup step). Another cleanup step is created following that one.
No other card is named in this ruling.