I love the special touches he brought to the character of Ennis: his "chewing" and spitting, his "huhs" and "hunhs" (see below) and especially, his reversal of the shirts (Jack's sheltering Ennis's when first seen, Ennis's sheltering Jack's when last seen).
TWENTY OF 'EM!! (I just brought this over with us from IMDb so everyone feels a little more at home).
1) 00:16:40 Yeah, and what if Aguirre finds out, huh?
2) 00:20:28 If you don't get stomped winnin' it, huh?
3) 00:36:09 Well, what're we supposed to do now, huh?
4) 00:36:36 What if we need work from him again, huh?
5) 00:37:56 Well, that snow barely stuck an hour. Huh?
6) 00:38:14 I don't need your money. Huh?
7) 00:42:03 Well, I guess I'll see you around, huh?
00:43:18 What the f uck you lookin' at? Huh?
9) 00:49:00 I'll bet you could fix this place up real nice if you wanted to. Hmmm?
10) 00:49:39 This ain't so lonely now, is it? Hmmm?
11) 00:53:11 What about it? You wanna lose about half yer f uckin' teeth? Huh?
12) 01:02:18 Huh? (to Alma's "Maybe we could get a babysitter.")
13) 01:16:29 Well alright, long as I don't have to sing. Hmmm?
14) 01:20:04 What're you doing here, huh?
15) 01:41:42 You probably deserve it, huh?
16) 01:44:51 Jack, I gotta work. Huh?
17) 01:45:48 You been to Mexico, Jack Twist? Huh?
18) 01:48:35 Well now yer sleepin' on yer feet like a horse. (hmm?)
19) 02:03:47 He's a roughneck, huh?
Thanks to Spooky Rabbit for these...