This is what happens when you let disbelievers translate the Qur'an for you, while also ignoring half of the actual definitions in your own posted link and pretty much every other translation available. You should not let them do that.
Let's look at how this verse is actually translated elsewhere:
54 ومكروا ومكر الله والله خير الماكرين
— 'Ali `Imran 54
Sahih International
- And the disbelievers planned, but Allah planned. And Allah is the best of planners.
Muhsin Khan
- And they (disbelievers) plotted [to kill 'Iesa (Jesus) ], and Allah planned too. And Allah is the Best of the planners.
Pickthall
- And they (the disbelievers) schemed, and Allah schemed (against them): and Allah is the best of schemers.
Yusuf Ali
- And (the unbelievers) plotted and planned, and Allah too planned, and the best of planners is Allah.
Shakir
- And they planned and Allah (also) planned, and Allah is the best of planners.
Dr. Ghali
- And they schemed, and Allah schemed, and Allah is The Most Charitable of schemers.
Notice a pattern here? In particular, notice how none of these translations willfully chose the least charitable possible translation of ماكرين to make Allah look bad, which is a tactic often used by the unbelievers to discredit Islam.
Even your own link includes many possible interpretations, including "artful", "crafty", "cunning", "designing", "clever" and so forth.
But getting back to the core question: "Is Allah the best deceiver?" Obviously, Allah is the best at everything, and to say that He is not "the best deceiver" would be to imply that someone is better than Him, or that He Himself could be deceived by His own creation. If it were actually His will to deceive someone, there would be nothing anyone could do about it. But even then, to think that being "the best deceiver" means that He somehow just goes around… deceiving people… for some reason… would completely miss the fact that Allah is also the Most Just, the Most Wise, the Most Gracious, the Most Merciful, etc. Insofar as Allah is perfect, anything He does would only be done for the most perfect of reasons.
And in context, the verse is very obviously just referring to how He is so far above the machinations of his enemies — those who think they are so clever that they can deceive the All-Creator of the Universe — and that their plans are nothing compared to His Majesty.