Hey y'all! I'm trying to recreate the building explosion that begins at 2:42 in this clip from Contra III.

https://www.youtube.com/watch?v=DoQBfWT4v28&t=159s

More specifically, I'd like to know how to efficiently animate the sprites of the building to recreate the sinking effect. Can anyone share a conventional approach to this?

just move it down with some extra sprites covering the part of the building you arent supposed to see

the building is indeed just moving down one tile at a time, but a lot happens that hides the fact :

-the explosions : just regular bullet ones place at the bottom. Each of the 9 steps is 4 tiles, but only takes 1 tile in the sprite sheet due to mirroring.
Some similar effect could be achieved in pico-8 with just 2-3 tiles using pal() and palt(), and the same sprite mirroring tricks.

-the hiding : the down left triangular part is covered with sprites. Notice the pipes, some broken top pipes are added at the end, even if it makes little sense, since there are no pipes at the top of the building.

-the shaking : the background image stays fixed, but the foreground is moved up, then snapped back to normal at the same time the building is moved one tile down, to increasing the rumble effect. Use camera() between the drawing of the background and the foreground.

• the sound : an extra deep explosion sound each time the building moves one tile down.