Background: toC 25 heroic (or normal) could be very demanding instances in terms of shard, particularly in case several consecutives wipes
Before starting the event of floor collapse (before Anu'barak), you can have a free soul shard:
1) If you have no pet summoned, jump to 3)
2) if you have void/felguard/felhunter/succubus, stop the pet close to the wall of instance and run to the other side, you should dismiss the pet and get 1 shard back
3) Summon the imp
4) start the event, floor collapse
5) Get a free shard
6) Profit :P
P.