If I have 11 cards in hand and discard 4 lands during the cleanup step, how many times should The Gitrog Monster trigger (assuming I don't discard any further lands in the next cleanup step) and why?


The Gitrog Monster 3BG
Legendary Creature — Frog Horror
Deathtouch
At the beginning of your upkeep, sacrifice The Gitrog Monster unless you sacrifice a land.
You may play an additional land on each of your turns.
Whenever one or more land cards are put into your graveyard from anywhere, draw a card.
6 / 6

Reason I ask is that as written, 514.1 Seems to indicate one event for discarding. I watched this happen on a stream earlier and there were 4 triggers. I know that MTGO isn't always right, but twitch chat and the streamer insisted that this was correct and that each card was discarded individually. I couldn't find a rule to support that so I am asking here.

514.1. First, if the active player’s hand contains more cards than his or her maximum hand size
(normally seven), he or she discards enough cards to reduce his or her hand size to that number.
This turn-based action doesn’t use the stack.

All the cards the active player discards to reduce their hand size to the maximum are discarded simultaneously; The Gitrog Monster will trigger only once, no matter how many of those cards are lands.

If MTGO is behaving otherwise, it is incorrect.