IMO, the molly defuse is the most iconic and rarest among all because it'll most probably never happen again on big stage. Imagine this, the molly was thrown on the bomb but not exactly on it, CT starts defusing but molly spreads halfway through defuse and the CT dies from molly as soon as the Bomb is defused successfully.
Did you imagine it? Yeah OLOF already did that in major.
Sure, there's a luck factor involved in this play but so is the case with most of the iconic plays that has the graffiti for it.