An ability that triggers when a creature "leaves the battlefield" will trigger twice if that creature leaves the battlefield by dying
Just be sure that if youre going to play it to have the text ready on your phone so you dont forget it
While it's likely a bad fit for your K'rrik, Son of Yawgmoth storm deck and other black decks that aren't running many creatures, Contamination is perfect for commanders like Nath of the Gilt-Leaf that can play green mana dorks and reliably produce creatures to sacrifice to keep it around
Most of my Commander decks usually have 4-5, occasionally moving up as high as 6 board wipes if they need an extra out against decks that swarm the table with creatures or artifacts
The other Booster Fun variants are inserted at slightly higher rates than listed below to make up the difference
Bilbo, Retired Burglar Bilbo, Retired Burglar is seemingly a good choice for a Ring-bearer because it adds an additional combat ability to the mix, though I do wish there was more guidance of where to take the 99