Earn a laser spree in a single matchmaking game.

earn a overkill in a multiplayer game.

earn an Extermination in an Invasion game.

Number of winning games streak:
Tin:         4 games
Bronze : 6 games
Silver:     8 games
Gold:      10 games
Onyx:      15 games

-  In a Big Bro Slayer game get a "Broseidon" with a min. of 15 kills.

-  In a Swat game get a "Killtacular" and a "Killing Spree" with at least 10 kills, with at least 5 headshots.

In a MM game (any gametype) get  kills with a Plasma Pistol:
Bronze : 5 kills
Silver:     8 kills
Gold:      10 kills
Onyx:      15 kills

and have your weapon of destruction be the Plasma Pistol.

Handyman
"Get an assist spree in MM"

YAY... My most recent two have made it in.

In Score attack or firefight get a killionaire

Bronze: 2
Silver: 3
Gold: 4
Onyx: 5

TheKingR said:

In Score attack or firefight get a killionaire

Bronze: 2
Silver: 3
Gold: 4
Onyx: 5

I like this idea very much. Probably should make 4 the max instead of 5 though. 5 killionares is 50 enemies. Thats practacly 1/2 of all the enemies.

In a Score Attack match earn at least 13 sprees without dying. - Spree-day the 13th

I know this can be done since 100 kills gets you 6, then you have the ordinance drops, sniper & laser, shotgun you can another 3 and splatters, another 3.  I figure 13 gives enough wiggle room so you don't HAVE to get every single possible spree but it is still a good challenge.

DDRfreak0687 said:

In a Score Attack match earn at least 13 sprees without dying. - Spree-day the 13th

I know this can be done since 100 kills gets you 6, then you have the ordinance drops, sniper & laser, shotgun you can another 3 and splatters, another 3.  I figure 13 gives enough wiggle room so you don't HAVE to get every single possible spree but it is still a good challenge.

I like this one.  Noted :)

Blind Delivery Man
Complete The Pillar of Autumn with the blind and cloud skulls turned on heroic or harder. Get par score as always and die no more than 3 times

Earn a Second Gunman Medal (15 assist spree) during a campaign mission on Heroic or harder and meet the par score. - Here, I Softened Him Up for You.

I think this would truly be challenging.  Personally I find it hard to get assists in Campaign (only managed one Assist Spree ever) and judging from other player's stats I'd say its about the same all around.

EDIT: I thought of another one.

Earn a Sticky Spree in any Match Making Playlist - You Got Something on You, and It's Not a Spider.

I love plasma grenades, I've only manged one of these and that was on someone who wasn't playing and it was still really frickin hard.

get 10 assassinations in any mm game

get a wrecking crew (15 hammer kills) in grifball with less than 15 deaths
(less deaths idk)