Umm what seal? Seal of deflection, seal of the damned, seal of lightning?? All are available from the marketplace. Seal of the damned costs nobility, others gold. Also seal of damned has a chance to drop from certain eb's. check wulfs eb guide under guides. Ill get link real quick.
It's used to initiate the eb (Epic Battle), hte, haunting: the escape. This eb is similar to a regular haunting but has an extra 94.5k on phase 1 and pays 3x the amount of a regular haunt. Any further questions as small as this one, please refrain from posting in forums as it clogs forums up and there is no need for threads such as these, almost anyone in wc would know, post a few walls if needed.
When you need to close an envelope u lick it and then close it. That process is called "sealing" the envelope.
In addition to what 3B said, these seals drop from certain ebs or can be purchased for 59 nobility. You can see if you have one by going to the market place. They're listed under defense items (even though they aren't used like other defense items).
I assume you're talking about a Seal of the Damned. It's an item that's required to open the eb Haunting The Escape. It's basically a Haunting that pays 3x the normal amount. You can get it by either purchasing it with nobility, earning it in a drop from certain EBs(check wulfs eb guide), or earning one in an event like the 2014 Dragon Melee event(see the thread in the Event section of the forums for more details. To see if you have one, check in your defense pots section in the market place or on your profile. For any future small questions, please post here. viewtopic.php?f=3&t=2754 /lock