Since I'm also the lazy type when it comes to reading game manuals, I will shortly try to answer you question. A contigency and a sequencer are both spell you cast, and then you can store other spells within. A contingency is for storing spells with yourself as target, (thus mostly defensive spells) and is automatically triggerd when the criteria you specify is fulfilled, ie when you have lost 50% of your HP or when you are attacked. A sequencer is for storing offensive spells and this can be cast like any other spells. Thus you can store ie several magic missiles, but cast them all at the same time for increased damage. Very handy! Hope this helped.
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