Let's say you've played 1k a few times, enough to feel the potential rush through you. You know blanks are very powerful, while +100,000,000 point cards put a target on your back, but the next question you should ask (other than "Am I a munchkin?") is "What tactics can I employ to make the game easier to win?"
Instead of doing the seemingly common sense play of playing a Mega-Point card on yourself, play it on another player. This should buy you some time to make undercover plays while the other players battle it out on where the card should go. A word to the wise: Don't play this if it's a 2 player game.
Your opponent plays a horrifically overpowered card. That doesn't seem fair! And since they played the Caffeine card, can play 2 cards per turn, which they use to make the first card unable to be discarded, removed, destroyed, eaten, or otherwise taken from their control!
Well, what if you made that card their ultimate demise?
For example, if it's a Mega-point card, just throw a sign change card into the mix!
This tactic makes what at first glance seem to be an impossible puzzle for you to solve, now becomes the same puzzle for them, only this time you'll probably have the backing of all the other players and their blank cards.
Let's face it, what you have in your area probably isn't the best. The other players probably have better stuff than you. Luckily, you catch a break, or rather a blank, and you decide to turn the tides a bit. The No-Cloning Theorem may apply to real life, but this is 1k gosh darnit!
Create a card which can clone other cards and puts them under your control.
The difference between cloning a card and outright stealing it is that the owner of the card you're cloning will generally be more alright with both of you having the same card rather than you having the card exclusively. In addition, stealing the card may lead to a Counter War, and no one wants that. Generally, the cloning card should have some restriction to it, lest it either be suck-worthy or cause unforseen effects.
The Cake Bomb
(This is taken directly from this article)
Probably the simplest of them all, and thus the easiest to set up, the Cake Bomb method is, however, limited in its usefulness when the win condition has changed. It's also likely to be immensely annoying to the other players if you use it too much.
It works like this: You first create a card that adds a large and considerable amount of points, but not large enough to make it turn into a Giant Red HIT ME Target. Say, 1000-20000. The important part is that the card must say that the points must be awarded AT THE END OF THE GAME.
It's perfect. This single card is likely to be seen as unimportant by the other players.
Then, to pull it off, you simply play a Rezero when there are no blanks left in the deck. Most likely, everyone will end with a near-zero score while you have the 1000-20000 you got from the card earlier.
Teaming Up with others
Wouldn't this game be easier if it was team based rather than a free for all? Wouldn't it be really easy if it was one monolithic team vs one player? Create a "Team Up" card, where you get to team up with as many players as you want. Being a team has major advantages, mainly you all win together so you're incentivized to work together.
If you're really devilish, create a backstab card last-second and play it on your turn, which causes you to be the solo victor should your team win.