MODOK, doomsday chair, Captain America

[firbison]

MODOK's doomsday chain reads after this attack has resolved it can make another doomsday chair attack. Does the first attack resole and get to step 14b and then make another attack or does the second attack still resolve within the first attacks time "table". 

Would Captain America's bodyguard and vibranium shield being reactive superpowers being able to trigger multiple times during this attack?

Similarly would Captain America's bodyguard and vibranium shield being reactive superpowers being able to trigger multiple times during a beam attack?

[Thoras]

3 hours ago, firbison said:

MODOK's doomsday chain reads after this attack has resolved it can make another doomsday chair attack. Does the first attack resole and get to step 14b and then make another attack or does the second attack still resolve within the first attacks time "table"

Both.
The first attack resolves and gets to 14a, at which point M.O.D.O.K. can make an additional attack. This additional attack occurs within the resolution of the first attack, meaning the additional attack will be entirely finished before the first attack is finished.

You will get to 14a with the first attack.

You will then start again at step 1 for the additional attack and proceed all the way through to 14c for this additional attack.

You will then go back to 14a of the first attack and resolve any other 14a rules triggered/resolving during it.

You will then finish 14b & 14c of the first attack.

3 hours ago, firbison said:

Would Captain America's bodyguard and vibranium shield being reactive superpowers being able to trigger multiple times during this attack?

They are each a separate attack even though one is occurring within the resolution of the other. So no, they don't trigger multiple times during a single attack, but you can trigger them for both the original attack and the additional attack, assuming you meet the criteria.

3 hours ago, firbison said:

Similarly would Captain America's bodyguard and vibranium shield being reactive superpowers being able to trigger multiple times during a beam attack?

Beam or Area attacks are a series of individual attacks, so yes, you may trigger them during each of the individual attacks, again, assuming you meet the criteria.