603.10. Normally, objects that exist immediately after an event are checked to see if the event matched any trigger conditions, and continuous effects that exist at that time are used to determine what the trigger conditions are and what the objects involved in the event look like. However, some triggered abilities are exceptions to this rule; the game "looks back in time" to determine if those abilities trigger, using the existence of those abilities and the appearance of objects immediately prior to the event. The list of exceptions is as follows:
The triggered ability of The Gitrog Monster is NOT a "look back in time" triiger. So I checked if the ability exists after the event, and the answer is no because the monster is already in the graveyard after Obliterate. So I guess its ability won't trigger, does it?
An ability of the form "Whenever one or more land cards are put into your graveyard from anywhere, ..." (such as The Gitrog Monster's last ability) isn't a leaves-the-battlefield ability (C.R. 603.6c) and is not otherwise an ability that "looks back in time" under C.R. 603.10a-g. Thus, for example, if The Gitrog Monster goes to the graveyard from the battlefield at the same time as one or more other permanents do, The Gitrog Monster's last ability won't trigger upon one or more of those permanents going to the graveyard as land cards this way, since The Gitrog Monster won't be on the battlefield immediately after it goes to the graveyard at the same time as those other permanents (C.R. 603.10, 112.6).
Opponent cast Obliterate, which destroys my monster and all lands.
Would The Gitrog Monster trigger for lands put into graveyard?
The triggered ability of The Gitrog Monster is NOT a "look back in time" triiger. So I checked if the ability exists after the event, and the answer is no because the monster is already in the graveyard after Obliterate. So I guess its ability won't trigger, does it?
EDIT: Edited after comment 4 was posted.
I noticed because this blog:
https://blogs.magicjudges.org/rulestips/2019/02/teysa-karlov-what-does-she-double/
One of the cases is Turntimber Sower, animated Treetop Village, and Teysa Karlov meet Damnation. The blog says that sower would only trigger once, Now I can say it won't trigger at all.