Rebuilding k'rrik need help with combo pieces

[Varatius]

So I want to rebuild my k'rrik deck this time I want it to have a focus on combo with chainer, dementia master and good old Gary and phyrexian alter to mitigate some of the black mana as well as be the main sac outlet I was hoping to find atleast 2 other creatures that work well doing this they need to atleast gain me 7+ life per trigger and I want to keep a rough budget of no more than $20 per card for the combo.  I'll also be running good ole mikeaus the unhallowed and  walking ballista for a back up what would you suggest?

[WWolfe]

Have you considered running Triskelion for redundancy as it too combos with Mikaeus, the Unhallowed?

[Varatius]

 I've thought about triskelion but I want to focus on chainer combos first because I enjoy the complicated build up being as I don't plan to have it be a competitive deck and I feel that having more combos will just encourage me to build it too strong for the play group I intend playing it in.