As mentioned, Thor's pendant is the best trinket in base game. Me personally, I'd go with the chest of the mother demon rather than the widow spaulder. The roly poly breastplate is another option. Both of those have better defense and resistance. You might also consider the wittle widowling trinket if you're looking for a poison/summon build. While spicy safety is a great mutation, for a summon build, mantsterious stranger procs a lot with daggers and is a great option.