In your eternal memorie

Each time a creature loose it's linked SoulBond,
create a token artefact "anonymous memorial"
with "give to it's linked SoulBond +2/+2.", then
linked it to the creature like a compatible
SoulBond.
At the begin of your turn, if you have 5 or more "anonymous memorial" you can summon
"Solten, the endless lamentation", from
everywhere without pay is mana cost.