The demo is 30 minutes of online play and limitless offline games against bots (you can't use splitscreen for offline games with the demo, though). Hopefully you can get at least a couple of decent games online. If you have a team you don't want to play with again then make sure to not just use the character select screen they dump you back into after the match immediately since doing so pairs you up with the same team again.
I've actually changed back to Dynamite since. You really do need the area and burst damage it provides. You should be able to get both extra sticks and an explode on contact (Rubber Sleeve or Contact Detonator, I use Rubber Sleeve) upgrade fairly early on, so there isn't too much to worry about. With Piggy Bank you can afford to start off with one of the extra stick upgrades so you should be alright while you don't those other two essential dynamite upgrades. From there, I'll usually start upgrading the Bull. With Cattle Rebooter (Shorter CD for Bull, same as Dynamite after upgrade) and Super Breed (More health, more knockback) you have a pretty good makshift minipush against turrets, since you can get some good damage in with 3x Dynamite in that time. Breaking up groups with the Bull isn't all that effective. They'll regroup pretty quickly and you won't have much to show for it. There's not really anything set after that, and if I felt I needed to I could definitely insert some upgrades between Dynamite and Bull. I've found that I usually need to get defensive upgrades at this point, health or speed. Mister TNT (Larger area for Dynamite) is something I'll want to get upgraded too, since it helps even more against enemy groups. Might still swap it out for Transfusion, but probably not. Damage/Rate of Fire upgrades for the Blaster come very lategame.
Other character just don't have the area damage that Lonestar does. He's very good at getting groups to scramble just enough that other characters can potentially get some kills, since he can do it from such a safe distance. Dynamite's angle can help with this since you can attack effectively from midair platforms. The middle of AI Station 404 and the platforms closest to the top turrets on Sorona are good examples. Lonestar is also able to push turrets with minimal bots, another rather unique ability.
I like to play Clunk really, really dumb. Get Homing Sensors, Free Flight Fins (Speed and Rate of Fire), and the Salvo Value Pack (or Fat Pete if I don't have that unlocked) and use your high health to your advantage. If someone tries to challenge you too much, explode on them in defense. Get some max HP boosts and use Bite to keep your health up/raise the max with Medical Pump. Then again, I've already changed my mind on how Lonestar should be played at least 3 times or something, and I've played Clunk way less, so...
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[NO BARKLEY NO PEACE]
im here to you dark soul with my LIGHT -ertyu