Oh… I missed this before:
“and its parody”? TH2AD isn’t a parody 
Its OP is a parody of TH2’s OP…
I don’t remember many Game Openings right now, but one thing i know: I just LOVE Game OPs with songs by I’ve Sound! 
EDIT:
One i remember i liked very much is the Opening and Ending of SNOW DROP mainly because the beautiful songs. :lol:
Another is the OP of ANEIMO 2.
There’s these OPs too:
FATE-STAY NIGHT PC Game Opening - Version 1, Version 2;
FATE-STAY NIGHT REALTA NUA PS2 Game Opening - Version 1, Version 2.
Urgh… i just remembered how much i love I’ve Sound, and how much i hate Emiya Shirou! :roll:
The instrumental-only (the first 45 seconds) part of the GSS op song is sweet. (a bit insane, but sweet)