All adds need to die before you can start placing shards. The Light Blue and Purple Shards can be hard to distinguish. What I like to do is just place them based on the one closest to eachother. Meaning I put the Green Shard in the Light Blue and the Light Blue in the Green. Then I place the Red in the Purple and the Purple in the Red. When the adds disappear and drop the box just use the same shard on that exact pedastal.
Update to this topic. The shard you place on the altar has to be DIFFERENT than the color in the window. You will get a message that says something to the effect of a "Mis-matched shard has collapsed the portal". The add will disappear and you will get a chest you can loot.
The submissions has been updated to reflect this.
When you have the cycle going you might only get one add every now and then since when you use a shard on one of the pedastals a chest drops with a shard in it. Only because of timing issues will you get an add once in awhile. Then again if you have enough dps, you might not get any.
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Merged Double Post
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Arcane Maelstom is a 42 second Timer that is NOT-Swipeable.
Polar Avalanche is nothing really to be concerned about.