Ignoring things that ignore the ignoring of...

[Foxwarrior]

A punch elemental doesn't have a glass jaw, obviously its chin is a fist

[deaddmwalking]

A punch elemental doesn't have a glass jaw, obviously its chin is a fist

Behold a punch elemental:

[gatorized2]

For what it's worth, I like the way Prowlers and Paragons handles immunities. The standard way is to just buy the immunity you want, and there are no immunity override mechanics. There are ten damage types; in my games, I limit a character to no more than three damage type immunities (I've never actually seen a character take more than one, and most don't take any).

Then there are the conditional immunities, mainly energy absorption - immune to any energy attack of the chosen type whose rank doesn't exceed EA rank (and it's a passive defense if the attack does exceed your rank), and armor - immune to any non-mental attack whose rank doesn't exceed half your armor rank (and it's a passive defense against all non-mental attacks).