A fun deck I enjoy playing a lot.

The strategy is to have a lot of creatures with Enter the Battlefield effects + Lumbering Battlement.
Justiciar's Portal to protect something or to trigger an effect again.
Thud + Lumbering Battlement as finisher
Mirror March for the overkill and Memes.

Any suggestions of cards that could also fit in?

//Update: 13.03.2019

4x Seekers' Squire
4x Dusk Legion Zealot
2x Skymarch Bloodletter
4x Militia Bugler
4x Ravenous Chupacabra
2x Basilica Bell-Haunt
2x Gravedigger
3x Lumbering Battlement

2x Ajani's Welcome
2x Mirror March

2x Thud
3x Justiciar's Portal
1x Slaughter the Strong

4x Plains
4x Swamp
4x Godless Shrine
4x Isolated Chapel
2x Blood Crypt
2x Dragonskull Summit
4x Clifftop Retreat

I'm playing a similar strategy but bant. I use guardian project, so everytime I portal a creature not only am I wasting their removal spell, but also getting the etb and drawing a card, sometimes two. Once it gets rolling it's a blast to play.

I know memes are kinda cool, but to make this work more consistently don't you need 1-2 more Lumbering Battlement (in stead of Mirror March, probably)? Otherwise cool idea.

Yeah I would add 1 more Lumbering Battlement (but I don't want to waste rare WCs).
Not sure about 4, unless you go for an infinite loop strategy.