Everything listed here only happens on heroic. All of them happen at rather early stages of each fight making them a decent way of recognizing heroic modes.
The Spirit Kings Heroic:
The encounters first boss uses it at the first minute of the fight. spellId 117961 Impervious Shield event SPELL_CAST_START
This ability is applied to players who soak the damage of Total Annihilation: spellId 132222 Destabilizing Energies event SPELL_AURA_APPLIED
If the previous event is not applied to some people after Total Annihilation then this other event occurs: 127341 Catastrophic Anomaly event SPELL_DAMAGE this will most likely wipe the raid
Will of the Emperor:
Unit GUID: 60480 Titan Spark, this unit is only present on heroic, it spawns from every add that is killed throughout the fight.
PS: If you need logs, send me a PM or look at my guilds parses.
PS2: Let me know if there is any way I can help improving heroic detection in the future ( for example I can supply heroic PTR logs, or live logs at early stages of content availability )