Megatron - Decepticon Leader in bot mode has a total of Pierce 6 due to his ability and the upgrade equipped (Crushing Threads) and attacks with a total of 5 regular attack damage. Prowl has (Force Field) equipped and defends for a total of 2 because no blue pips were revealed. Force Field does not trigger because the attack damage did not exceed the 5 and higher damage limit. Is this right? Does he take 3 regular damage or 6 pierce damage?

Because Megatron has Pierce 6, he would do 5 attack damage (remember that attack damage can’t be higher than the character’s attack, even with pierce). This causes the Force Field to trigger, so instead, he’ll do 4 damage and the Force Field will be scrapped.

Common Megatron is in Bot mode. He has Grenade Launcher equipped giving him +4 attack. He attacks Barrage in Bot mode. Megatron does not flip any orange icons and Barrage does not flip any blue icons. Megatron's attack is 8 w/Pierce 3 (due to his ability), while Barrage has 2 defense. Does he only deal 6 damage for the entire attack or 3 only due to his Pierce 3?

6. Pierce is a minimum damage.

Jazz in Alt Mode is defending against Megatron - Decepticon Leader in Bot Mode. They flip no extra oranges on attack, and I flip 4 white on defense. Does Jazz then take 3 (because of the Pierce 3 minimum) or 4 (because the Pierce completely nullifies the ability)?

4. Pierce completely nullifies Jazz’s ability.

Regarding character triggers, the following scenario is Demolisher/Darkmount/Common Megatron all in bot mode. I play Brainstorm > Hunker Down > Rapid Conversion. Hunker Down flips all 3 to alt mode, then I play armors from the scrap pile if able. Once Hunker Down is complete, I play Rapid Conversion targeting Megatron to flip him into bot mode. Brainstorm is now resolved. Moving on to character triggers, would Demolisher’s ability now draw 1 or 2 cards? Would I be allowed to use Megatron’s flip ability?

In this scenario, Demolisher’s ability would draw 1 card and you would be able to use Megatron’s flip ability.