In a multiplayer format like Commander, people are going to cast a lot of spells, and they're all going to make Ishai bigger
Witness Protection A simple nullify effect that deals with indestructible creatures for just 1 mana is a great deal for any commander player
Unstable Glyphbridge leaves behind only a creature with power 2 or less, and its very good in formats like EDH when you want to wrath the board and leave your small commander around
God-Eternal Rhonas has deathtouch and the ability to double the power of all your current creatures on the battlefield until the end of the turn, while at the same time giving them vigilance
It can hit the field on turn 3, and the following turns chapter ability lets you pod a creature for any other creature or basic land, and then put it into your hand
The milling attack trigger is what gets me going