1. Push it to the limit



Animation from Scott Pilgrim vs. the World: The Game

2. Make everything bouncy and feel alive



Idle animation for Mercenary Kings boss

3. Create strong key frames and silhouettes



Super Gem Fighter Mini Mix's Sakura, courtesy of GSA

4. Try to limit your frames



More animations from Mercenary Kings

5. Don't fret too much over the craft



Paul Robertson's "Irem vs Taito" art for Super IAM8BIT

In this era dominated by 3D games, when even the latest versions of Street Fighter and Super Mario Bros. are made up of polygonized characters, quality sprite-based 2D games are rare.Many now consider the process behind making beautifully animated productions like Metal Slug or Aladdin to be a lost art, forgotten and undervalued as developers chased the excitement and economy of 3D graphics.But there are still a handful of gorgeous sprite-based games that release every once in a blue moon, and a few have had the fingerprints of animator Paul Robertson all over them, like Ubisoft Montreal's highly-regarded Scott Pilgrim vs. the World: The Game.Robertson's style is immediately recognizable, featuring short and stocky figures that look like River City Ransom characters brought up to modern standards, with much more detail and personality packed into each frame.His latest work can be found in Mercenary Kings , a soon-to-be-Kickstartered 2D run'n gun developed by the Ubisoft Montreal veterans at Tribute Games (Wizorb). Jonathan "Persona-sama" Kim, also an animator on Scott Pilgrim and other titles like Skullgirls, is on board for the PC title, too.There are already plenty of tutorials and discussion threads about the technical aspects of making pixel art out there -- so Kim and Robertson shared some general advice for animating game sprites that really stand out and leave players wanting to see more.According to Kim, most people working on sprite-based 2D games nowadays tend to not push their animations enough. You can blame that on a number of reasons -- time and/or budget constraints, artists settling early and wanting to rush to the next set of sprites, etc. -- but the results are uninteresting poses and forgettable animations."I just try to make the most awesome and ridiculous thing I can think of," explains Robertson. "I always imagine other people's reaction when they look at something I've done, and if it seems underwhelming I'll push it further or add more to it till I think it's good enough. Actually this works for any art, not just pixels."Of course, you don't want to overwork an animation to the point where it looks too busy and takes away from what's supposed to be communicated by the movement. That's why it's useful to have someone to show your work to, and who can say whether you need to tone it down or push it more.Part of pushing your animations is making sure that characters never appear stiff, or as if they're made up of independent moving parts. Even when animating something as simple as a person breathing, you need to do more than just move their chest up and call it a day.Robertson says that you should always try to keep the character moving, even if they're standing still. Add some bounce to your characters, move their fists, make them blink, and add whatever you can so they look like they're living, breathing sprites."[You have to animate] things like hair and clothes blowing in the wind or swaying around while they move, giving them exaggerated facial expressions, cute or funny idle animations, anything that makes them feel like they have a personality," he adds.When it comes to animating your sprites, Robertson says "The most important thing is to have really strong and extreme key frames. It doesn't matter how smooth the animation is, if it doesn't have awesome keys, it'll still look shoddy."He points out that a lot of older sprite-based games have only one- or two-frame animations, but they still hold up well. Capcom's Super Gem Fighter Mini Mix (Pocket Fighter in Japan) is a great example of this, with its characters growing huge, pulling out weapons, or changing their look completely in a couple of frames.For those without formal animation training and a grasp of its principles, Kim advises they master silhouettes: "You have to be careful about the negative space. Make sure everything reads from just looking at it against a white background. You don't want an arm to be inside the torso area, and you can't tell what's going on."Artists can be tempted at times to add too many frames to their animations sometimes, telling themselves, "Oh, maybe this could use one or two more breakdown frames." But it's best not to over-flourish your animations, limiting the amount of frames and just using a good smear instead, to ensure the impact of the movement isn't lost.Going overboard with your frames can also ruin the timing and tone of a character. "That's the main problem with animation for games, you can't make it good for just the animation's sake," says Kim. "The first purpose it has to serve is for gameplay, and then afterwards to make it as good-looking as possible."Fans and animators of sprite-based games can sometimes fetishize pixel art, and care too much about the craft than the actual content. Kim says this can be particularly annoying when you upload your work and look for critiques from artists in online communities."People can be all like, 'Hey, that's too many colors for what kind of effect you're trying to do.' And it's like, 'No, you guys are caring too much about particular details instead of looking at the whole picture or what the image is trying to represent.'"If you want to learn more about making great game animations, Robertson says the best way is to play classic games from developers like Taito and Irem, watch entire animated movies frame-by-frame, take relevant educational courses, and read Ollie Johnston and Frank Thomas' The Illusion of Life: Disney Animation